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ONKYO integra A-8760 hi-fi amplifier r&r project

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This is a nice new r&r project of a high quality power amplifier (made in japan) ONKYO integra A-8760, a beast from the late 80’s !


There is a whole story about how I got this amplifier, it was offered as a gift, non-working unit, spare parts only, you name it. One thing was for sure, it has 14kg and as far as I could see it didn’t have any noticeable plastic parts, it may sound funny but these are the best things you should consider on an amplifier(or other product if you ask me), you don’t have to be an audiophile or whatever, just take your weighing device with you and that is it! 🙂

“Under the bonnet” I found a huge linear power source with a nicely shielded transformer and two big caps, that is the heart of any amplifier and it matters a lot, it is like the engine of a car, the bigger it is, the better it sounds 🙂


The tuning age is at it’s best, just look what a nice upgrade I found inside this amp, a led bar and a couple of fans, they hit the dumpster in no time!


The amp powered on but there was no output from speaker terminals, I noticed some burned electronic components, let the fun begin! Take a look at the main fuse that I found, can’t be bigger than this :


As you are already familiar with analogicsound’s projects this project also required the service manual, it was absolutely necessary. Of course that huge power source was ok(even if inappropriate fuses were used) , in fact the amplifier powered on just fine, the problem was not in there. If you replace a fuse with a good one and it blows again you should never install a bigger one(or a golden one 🙂 ), that is just stupid and can add extensive damage to any device, you just have to repair that device or use the dumpster.

I must say that this amp suffers from cracked solder issue, a lot of devices from the 80’s and 90’s suffer from this, age is age and bad solder issue is indeed a huge source of problems, I decided to resolder all components, the preamplifier was badly affected but other modules had problems also.




After this time consuming job there were no big improvements, almost all transistors from the final stage were shot, a lot of power resistors were damaged also, most of them read high impedance, further analysis were necessary. A big problem is that original transistors (made by Sanken) in Japan are hard to find, of course cheap chinese components are always on the market but for this amp I wanted the best transistors “made in japan”, no budget repair!

This is gold(thank you @brain 😉 )!


One thing that I love about this amplifier is that is quite serviceable. It has separate modules and a lot of space between components, no SMD, high quality capacitors and high quality japanese design from the golden age of hi-fi, it is a pleasure to work on it!

Here are the final stage transistors:


All final stage transistors were replaced (as pairs) and all related components were checked and replaced if necessary, biggest problem were out of range components, like resistors who suffer a lot when  a short circuit is happening, this resistor supposed to be 2.2kohm and now it reads almost 3kohm:


Various replaced components:

IMG_20160719_134845 IMG_20160718_095945

After all these steps the amplifier was ready for tests, DC voltage protection was checked and idle current was adjusted within specs.


Then the speakers were connected, normal operation and all functions&inputs were tested, the repair was a success!


Thanks for reading, more r&r projects will be available soon, the project will be advertised on facebook, thanks to all who liked this !






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July 20th, 2016 at 8:47 pm

another Pioneer PL-L1000 r&r (complex)

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Time for another Pioneer PL-L1000 repair!

One day a customer/friend came to us and brought another PL-L1000 (non-functional unit):


The deck looked ok, minor scratches, no dents but it was not working properly. I noticed that this was not one of the military versions as it had only 2 voltage selector 220v/240v, so the power transformer must be ok, you have to adjust the selector to match the line voltage in the location you are using the unit, and if the deck is set to 120v AC(japan)and you plug it to 220v AC (europe), damage may occur but this was not the case, in fact the deck powered on just fine!


All repairs requires the service manual, but experience is also needed, testing the main functions of the deck showed that the main motor is working properly, the size of the disk cannot be selected, and the biggest problem was that the linear motor was not working when “start” was depressed, lead in sequence not performed. The lift motor was not operational though the display changed state when the lift button was depressed.


So we got busy!

First step was to check the mainboard and power supply for cracked solder joints and I also checked the voltages delivered, everything looked very good for a 40 years old turntable, the boards were totally resoldered just to be sure we don’t have any kind of contact/soldering issues.


The circuit is double sided, removing the components can be very challenging as the mainboard is very sensitive to heat, it may be due to it’s age but for sure you have to be moderate with the soldering tools, you don’t want to damage it!


The mechanical parts were cleaned, checked and adjusted to a “ready for testing” state, somebody did a big mess before me, adjusting all that you can imagine, including all variable resistors. A nice point to start is to have a picture of a functional unit to see if the variable resistors are way out of range, these decks are “made in japan” products, having constant production quality, automatically all adjustments must be in the same range, that is one proven theory that comes from experience, it may look like a hit&miss procedure but any kind of information must be considered, remember that there’s little to nonexistent information on the internet about repairing these beautiful decks – Pioneer Linear Tracking series.


It is always a good idea to take pictures/make your own schematics of the original setup, even if you know it’s not good, sometimes the wires are directly soldered on boards and over the years they become brittle and can come apart when moving the boards out of the way for repairs, these are old sleeping monsters with a little bit of life left in them!

Unfortunately none of these steps helped in improving the actual state of the turntable but we managed to isolate the problem, it’s the logic control that we have to restore, that’s why this is one beautiful nice repair project, isn’t it!

The logic control is made using discrete c-mos components, good news is that a lot of the integrated circuits are still available on-line at very low prices, we won’t find the original Toshiba “signature” chips but any equivalent chip will do it’s job very well, bringing life back in this high-tech beauty of the late 70’s!


I decided to solve the “disc size” mystery button, as mentioned earlier in this post, pressing the size button must switch between 7” 10” 12” disc size and our deck did nothing, only 12” size option was on all the time.


According to service manual, the disc size function is up to IC 15 wich is TC4027 (CD4027) which is a flip-flop circuit. For more information you can search the web, there are a lot of documents and applications for this C-MOS circuit. Keep in mind that these are ESD sensitive circuits,  you have to pay attention when you work on them.


After replacing the IC we had a functional disc size display!

The repair process is based on test points, checking the voltages (given in the service manual) while testing the functions it is mandatory.


Further analysis lead to replacing IC10 & IC 8 (lead in FF stage) and after that the turntable was alive, the logic control worked perfect!

IMG_20160509_124601 IMG_20160509_124557

One more thing was necessary, cleaning the cue(lift) motor and replacing the belt, the main motor (SHR-stable hanging rotor) received some oil also:

IMG_20160509_130548 IMG_20160509_130142 IMG_20160509_130403

Now the turntable is an old working beast, ready for a new audiophile experience.


Here is the cartridge for it(original cartridge was Pioneer PC600 but it was missing), a nice LOMC (moving coil) cartridge, Audio Technica AT312EP, a sweet setup:


Thanks for reading, more r&r projects will be available soon, stay tuned!






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May 9th, 2016 at 6:56 pm

Alfa Romeo Crosswagon Q4 seat heating r&r

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Here is a little post about how to repair OEM seat heating on Alfa Romeo Crosswagon Q4(same system may be present on other cars from Alfa Romeo from the same generation).

From the first hours of use(second hand vehicle) I noticed that the heating could not be felt on the right seat although the LED for ON operation was lit.

The driver’s seat was also a lazy heater, in winter time sometimes temperature drops to -20 Celsius, for sure you want your heating systems up’n’ready!

Here is a nice pic of the this car going off-road(me driving) in a beautiful winter landscape a few years ago(it has full time 4×4 transmission with a Torsen C center differential with dual locking stage and open rear/front differentials assisted by ASR) :


Here is the schematic of the seat heating, it is a simple system with 2 heating elements working in series, 1 thermostat and a pushbutton, a red LED is used to signal the ON state together with a small series resistor(located in the LED cable) .


A lot of users have non-operational seat heating systems because on these cars they are prone to fail but in fact the repair is always easy and cheap, making what is called a DIY job, you rarely see a broken heating element because they are pretty much protected by the leather of the seat and heating elements are solid as much as I could see.

Source no.1 of trouble(LED does not lit, heating doesn’t work) is the push-button, that is an easy fix, if the fuses are ok and the voltage is present under the seat and by pushing the ON button the heating does not work and the red LED near the seat does not lit than you must replace the button, no problems with that, easy job.

Source no.2 of trouble(LED is lit but heating doesn’t work) is the thermostatic element in the seat itself which is an old fashion bi-metal thermostat like the one in your electric boiler which opens its contact on a preset temperature, in our case I didn’t know which was the original temp setting and I am not curious about that, anyway it was not good if you ask me, never had really good heating in these seats but I suppose it was around 50 Celsius, decided to replace them with 70 Celsius new ones because the originals were burnt and they always failed to provide decent heating in cold seasons if they (ever) worked.

By using these new parts I am avoiding switching as much as possible, and if further control is necessary I will add PWM buttons replacing the original ones, using the 70 Celsius thermostat as a safety device, all new heating systems are built that way.

So here is the original thermostatic element, to find it you must take out the seat from the car and uncover a little the heating element of the seat in the back side of it, an ugly but not so hard to do it job because those metal rings that hold the leather to the seat are pretty strong, didn’t refit them, just used plastic ties on reassembly because everybody does that nowadays, plastic engineers are everywhere around and they just didn’t mentioned quitting yet 🙂 :


The original thermostat measured high impedance, and goes in it’s final place, the dumpster.

Here is the disassembled seat:



Here it goes the new thermostat:


Finally the system was tested and the wires were at last routed the good way in there, it was an Italian mess under my seat in the car:


Now that’s heating for 2 euros (one little Chinese thermostat 🙂 )!

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October 9th, 2015 at 8:01 pm

Webasto on Alfa Romeo crosswagon Q4

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This is a nice (long) project that applies to any Alfa Romeo 156/147/GT/crosswagon JTD, that will be posted here with a lot of details.
In winter time the need for comfort leads to heating and there is no upgrade like a FBH(fuel burning heater) in a diesel car, the idea is not new, a lot of cars have these upgrades nowadays as a factory setup, this post is useful for this specific application Alfa Romeo because it shows a nice new integration and introduces some new features which improves safety and comfort, features not seen before in other tutorials, a clean installation concept.

The goal is to have a remote, GSM controlled heater and the new idea is using the webasto water pump as an emergency water pump in case of an engine overheating situation, 1.9 JTD engines have problems with the design of the water pump, plastic age is at its best(plastic engineers), the impellers just separates from the metal shaft and the result is always engine overheating, a lot of users reported water pump failures, some users reported just engine overheating but that is the same thing, water pump failure.

Here is a picture showing a new pump (different impeller design) and the old pump with separated impeller:


When you want to do this upgrade to your car you must take into account:
-you must have basic electrics/electronics skill
-a lot of time…some say that time is money but vice-versa is always right when all things are working against you no matter what you do 😀

Step no.1 : the big purchase

In order to start the project you need some hardware, some may say you need suitable hardware, that being said a 5kw FBH(fuel burning heater) is all that you need, some producers have 3kw heating systems but we are heating water in this setup (not the air in the cabin) so a higher power unit is needed.
The heating system is used together with the climatic unit, the heater heats the primary water circuit and then the climatic unit of the car extracts the heat from the system and heats up the air in the cabin, that is so easy! 😀

As the electronics era evolved, the systems sometimes became over-engineered by means that producers try to protect their software and hardware, they even try to produce systems locked to a specific application.

However, when this is due to one reason, profit, I find myself difficult to credit their brilliant ideas. 😀

As an example, it is all the good in the world to have a heater that goes in protected mode when the fan doesn’t work, it prevents fire and hazardous situations but when this occurs due to a failure of identification of other additional hardware like presence of CAN bus or other things unnecessary for the heater to perform its main function, that is not good, and these things leads to market presence of other (chinese) manufacturers, fortunately only time is smarter on earth! 😀

With this type of software “customization” a lot of heaters, hundreds and thousands, can’t be used and they stay in the junkyards fully functional because they are not easy to start/unlock.
A lot of persons who activates in this domain recommends to stay away from OEM applications, some chinese pcbs can be used instead of original boards but that was not an option for me, no clones, reliable hardware only! 😀

An Audi Q7 Webasto Thermo Top C FBH was found with low hours, latest hardware and latest software, happy was I, here it is:

25471 (394)


The heater came with some pipes and hoses, you always need hoses, brackets and pipes in a DIY project like this, fittings/pipes are the hands of gods, any piece of hardware may prove useful, don’t throw away anything even after one year, you may need it the next day 😀

Step no.2 – “laboratory” initial tests 😀

Purchasing of the professional software and interfaces was considered, initial tests started on the bench, all components of the heater have been tested with success.



This particular model was used in Audi Q7 in conjunction with climatronic control, the pump of the webasto heater was actuated by the climatronic module of the car, long story short: reprogram the unit or make additional hardware changes for the water pump to start, otherwise overheating will occur and eventually heater would go in lock mode.

You can see here the connector for the water pump which is a false plug in my case:


The heater uses CAN-bus protocol to “talk” with the car in the original configuration and it also has w-bus for diagnostics(w-bus can be used for diagnostics and you can also start/use the heater) so you need a controller with W-bus, new style(more expensive) and that is the reason a lot of users choose old versions of webasto heaters which requires a hot wire(+12V) to start.

One bigger problem is that if the heater runs out of fuel or something, you have to hook up the diagnostic software and unlock the heater, I know it is about safety but I don’t like this at all.

The controller in this project is webasto oval timer 1533, it has 4 wires, 2 wires are for power, one is w-bus interface(heater startup) and one is a 12V+ ON wire used for older type heaters(heater startup, but I will use this output to power on climatic unit(and water pump) using an intermediary 12V relay) :


Here is a picture from the connector side, the picture is not mine, I found it on the internet, it doesn’t matter anyway, the timer comes with symbols on the back of the case, easy job.


My first setup was very interesting, it keeps original software of the heater, the water circulation pump is controlled by the oval timer 1533 from its analogic output, and the heater is controlled from the digital(w-bus) output of the same timer, simple as that, I really loved the setup, the pump had an override switch that powers the pump in continuous mode, this setup could be used for emergency situations when you need some water circulation, in case of water pump failure you can cool down your engine using the inside cabin heater, you may need this setup only once to save your engine, I don’t want to maximize it’s duty, but I really love backup hardware ready to be used when you need it the most, these kind of things are rare(to nonexistent) in today’s plastic toys, our daily drivers.

Here is the schematic that integrates the original Audi Q7 heater with no software modification, I had some problems with this setup, problems that forced me to update the firmware of the heater, but even after that update the same kind of problems appeared, than I searched and made a lot of tests and found that the update was not necessary, I will try to explain what the problem was and what mods are necessary to be done in order to have success.


I will also attach original alfa romeo schematics with the start circuit for the climatic unit, to start climatic unit you must provide a 12v wire from relay1(in my first schematic) to fuse F6 in B98 Supplementary fuse box 5505A, for more information about climatic unit schematics you can go to alfa156 forum (many thanks to user @Rob 156) :


Here is the same schematic with the timer and heater but it contains a switch(B1) which bypasses half of the Relay 1 for continuous water pump operation(in case of engine overheating due to main water pump failure). The B1 simple switch will be located inside the fuse box panel.

This schematic did worked on my car very nicely, but after a few runs, the heater stopped working, timer showed F–, it means fault, when I hooked up Thermo Test sofware, no errors but a strange CAN bus related error, that is why diode D1 appears in the schematics, it was added later in the final setup, it has a purpose.


Here is the error(customer specific fault), plastic is no kiddin’ 😀


More schematics will be posted, about GSM control but we will talk about that later in this post.

Is time for Step no.3 which is about heater mounting and all the hardware.

Imagine that from all (audi Q7) received parts a good friend of mine who sees cars in flesh and bones made a very, but very nice mounting bracket for my heater(MIG welding), I was so happy:





Believe it or not, I have never seen such a nice elastic heater bracket on Alfa Romeo!


As you can see the turbo actuator was relocated, it was such a tight installation!

I would like now to introduce a new chapter in this post:

Fuel supply!

What is the big deal, you have a pump, some hoses? No, it is not easy, on Crosswagon nothing is easy, just try to connect a hose to the fuel tank! Impossible, you have to take out the tank, remove the rear differential and other related stuff, just forget about it, how about installing a nice little dedicated tank in the return line in the engine compartment right under the fuel filter? Done.

The additional tank accommodates about 0.6 liters of diesel fuel , that is about an hour of operation at maximum setting of the heater, the timer has 30 minutes as an operational preset time, so it was ok for me, I would like to use the heater in the cold mornings, abuse will likely drain the battery, once you turn ON the ignition the additional tank becomes full again, additional tank is such a nice find in my case!


Here you can see its installation:


Diesel pumps…

My initial test pump was not a Webasto pump, I found a Eberspracher Airtronic pump an just used it to see how it works, it didn’t performed well, a lot of flame-out situations, lot of smoke, more study was necessary, chapter “heater pumps” requires big attention!

I would like to thank to Roy Murkin from Letonkinoisvarnish UK

They have a nice website, very useful even if they present Eberspracher heaters faults and pumps, they also have tests with Webasto pumps and they really explain everything clear to anybody who is interested in heater repairs or heater installation, I really love those guys!

You can also find nice garage charger step by step repairs just visiting their website, they are definitively doing a great job!

Long story short, in order to maintain air to fuel ratio, you have (at least) to use the right pump in the right application!

Pump needed to be changed, the Airtronic pump was replaced by a Thomas Magnete pump, which is compatible with Webasto Thermo Top C heater pump. Thomas Magnete is a high quality product manufacturer from Germany:


Some pumps also have filters, when buying second hand hardware is very important to do a proper maintenance, old diesel fuel can produce gunk or other related problems.

Position of the pump is very important in these installations and can modify the amount of pumped fuel or the possibility of air trap and pumps must be mechanically isolated using rubber brackets, the same thing applies to turbo actuator valves, they are sensitive to vibrations and mounting position ( “late night” engineers might not agree with that but that is a fact and is found in patent description of the device), always stick to manufacturer’s installation recommendation.

Air bubbles in fuel line may be due to a poor connection but some pump models can trap air from outside medium especially if they were dropped or the car suffered an accident, one easy way to find an air leak is to pressurize the pump from one side, block the other side and test it under water, some old pumps fitted under the car may have corrosion problems.

Water pumps…

Water pumps are fitted to provide water circulation, electronic controllers are built in because pumps use brushless motors with magnetic coupled impellers, however pumps are sensitive, you have to use high quality antifreeze, the cleanliness of the system is very important. Some pumps develop cracks because they are made from some sort of plastic and controller boards are affected by corrosion but water pumps can be considered maintenance free products, repairing them is not easy (though it can be done sometimes).
One pump worked if the impeller was at first turned by hand, one coil of the motor broke exactly at the terminal soldering point, few minutes later, after the coil terminal repair, pump started just perfect but that was just a lucky repair, a new pump is often the only way to solve a pump failure.


ECU boards…

The heart of the heater is its mainboard, the heaters are extremely simple devices but the most important thing is how the system is controlled, both for safety and comfort.

Old heaters back in 50’s were simple, controlled by simple old school thermostats but as time passed by electronics were more present, the heaters from the 80’s and 90’s had external control boxes with processors and relays, they were easy to diagnose, repair and maintain.

Nowadays relays vanished, solid state design took their place, they are cheaper to produce, lighter and more robust. However a failure rate exists, sophisticated electronic devices are sensitive to moisture, overheating and thermal stress and the most important for us they are more difficult to diagnose, repair. 😀

Here is the ECU board of my heater:


You can see the main processor which is programmed (with a sticker on it with software version), various FET transistors, a lot of SMD components.

First tests of my setup were very good but I had an error, the w-bus timer 1533 and the heater had some kind of compatibility problems, the timer showed F– and the Thermo Test software showed no heater problems but a CAN-bus error, a “customer specific fault”-F5h.
There is little to nonexistent information about these faults on the internet, I was in a hurry to solve it, I decided to change the firmware of the heater, though (you will see later in this post) that was not necessary.

I would like to thank to Serghei Pugachev from Kiev, Ukraine from who provided the firmware update for my heater, thank you sir!

The firmware allowed the use of the false plug for driving the water pump directly from the heater board, everything seemed ok but the timer showed again F–, no errors were present, heater was not locked, project was forgotten for a few(summer) months…

Every project has a story to tell, some automotive projects have a lot of bad luck I guess, but there are no bad projects, only bad days.

That was the moment when some nice advice came to my mind, I will always remember these nice words:

“The right combination of Knowledge, Training, Experience, Vehicle History, Appropriate questions, Serious thinking and sometimes a little Luck can make a seemingly impossible job have success!

Many times taking a break away from the problem vehicle for a day or two of quiet introspection can bring the solution to the forefront.”

These words belong to Scott (from a site dedicated to Audi Quattro enthusiasts) in his word about “The art of automotive repair”, this post is dedicated to them, they always provided help back when I was the owner of a 200T.

That car(Audi 200Turbo) had KE-Jetronic injection system, very complicated because there were a lot of mechanical adjustments of the system which had such a narrow band of adjustment. The electronic system worked good only if all mechanical adjustments were perfect. Owning a second hand vehicle with a partially working KE-Jetronic system is a big challenge to any experienced user.
The system is very interesting, it uses high pressure fuel pumps, fuel regulators, mechanical injectors, high pressure fuel hoses. Same system was used on various Porsche models and Lamborghini (Countach QV) back in the 80s, complicated systems, dealing with them and understanding them makes a nice experience which is unique, today’s systems are very different (and boring). 😀

Even the systems were not very reliable, high quality materials were used, and KE-Jetronic cars really ran smooth and nice(when there were no problems) 😀

Their website ( is one of the most documented about “old school” Audi models, the best ones!

One lucky day!

OK, more analysis had to be done, one day I took a look at W-bus protocol, I was interested how the heater works together with the timer, there is also a “protocol” menu in ThermoTest software where you can see the devices are communicating continuously in running mode!

In order to maintain the running status of the heater, the timer sends a string of characters keeping the heater running, I don’t want to make things look complicate, if a heater is not locked and receives those specific protocol samples it should run with no problems, why do I have running problems? because the protocol is bi-directional and the timer also receives information about heater status (errors), and when that happens it shows (F – -) on the display.

In my case that was happening for some can-bus related reasons and after firmware upgrade same problems appeared for no reason or error, I think it must be some kind of compatibility problems between heater and timer.

I decided to add a blocking diode to the w-bus line, so to make a unidirectional link, the timer would send running signal to the heater, if something wrong happens the heater will not run and I will have to hook up diagnostic to see what is wrong, there will be no more fault signals on the timer, to my surprise system worked perfect, no errors on the timer, for the first time I had a fully functional system, that was such a happy day with such a simple diode, sometimes life is simpler than we think and the same result can be obtained using different methods, for me that is the definition of life!

I will post some pictures with the integration of the heater system on my Alfa Romeo, one more thing still needs to be done, did I mentioned something about GSM control ? 😀

Here you can see the timer inside the car:





Here is the exhaust partially used to heat up the engine oil radiator, a picture from under the car shows the exhaust ports, please remind that this car has a special resistant fiber shield under the car, most Alfas have a plastic engine shield wich may be damaged by hot exhaust gas, there is a nice clearance between the silencer of the heater and other parts, everything has been done keeping safety as an important factor, using insulators, dampers to minimize vibration, interference and other engineering aspects!


A lot of heaters have problems in winter time, exhaust being blocked by the snow, this setup avoids that kind of problems, everything is protected, it can’t be hit or blocked.


Under the bonnet, notice the FBH intake:


The GSM controller used is from a home heating system, I had it and I decided to use it:


For more info about this controller you can go here:

The integration of the controller is very simple, The idea is not mine,I found it on Land Rover forums, basically you have to solder a couple of wires to the heat push-button of the oval timer and route them to the GSM controller:

webasto dialer 009

For more info about that you can go here:

A problem appeared, this particular GSM controller can be used only for on or off state, in my setup the simulation of a push-button was needed, the relay must go to on state, remain there for a second and then the contacts of the relay had to open again to simulate the pressing of the “heat me 30 min” button!

Here is a nice modification made by me, the relay’s coil goes in series with a capacitor , as long as the capacitor is charging, the relay stays on, after that period of time(max 1 sec) the current drops to zero and the relay opens even if the GSM controller is set to ON all the time.

GSM mod

on board modification of the GSM controller:


The only problem will be that I have to send 2 messages, one to start the heater, and one to reset the GSM control for the next startup, the start message is like : ” 1 ca” and for the next startup I have to send “1 cn” and then “1 ca” again, that is not a problem for me, the controller was for free and I adapted it for my car! 😀

For those who like dedicated plug and play gsm control for their heaters they can go to: a site dedicated to heater controls

That being said, wishes a Happy New Year to all who contributed in the development of this nice little project and offers it as a gift for all true “Alfisti” from Romania and all over the world, feel free to contact us for any kind of information you may need!

More r&r projects will be available soon, stay tuned!

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June 24th, 2015 at 8:03 pm

Alfa Romeo Crosswagon Q4 generator rebuild

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Here is a nice post related to one of my cars, Alfa Romeo Crosswagon Q4. I own this car since 4 years, bought it as a second hand vehicle but no generator maintenance/repair was mentioned in the service book, the generator received a new free-wheel pulley last year, mileage is about 200k so as a rule of thumb nasty things would happen at this mileage if we consider “the plastic age” as a fact.

We must say that the generator is badly ventilated in the engine compartment and is affected by heavy thermal stress and the most wrong thing, it is unfused(skunk mind failure), a lot of cars have a maxi-fuse which prevents battery shorts through alternator or undesired grounding of the alternator output(battery failure), rare events that have a huge fire hazard potential, you are a dead man cruising if something like that happens on road and the best thing to do if you hear a whining sound from the engine related or not to a battery symbol and you observe smoke from the engine/alternator is to disconnect the battery as soon as possible and try to save your car or yourself using a fire extinguisher.

Long story short, I survived, car survived, the alternator was analysed, the stator was in bad shape, the rectifier was shot, bearings, regulator, rotor, all good, it’s time for another r&r job, some people would like to use parts from scrapyards but this is not the case for me on a daily driver, I want my electric systems to be very good, reliable and with a well known service history.

Few pictures with the original stator:



The alternator failed because of the damaged rectifier by thermal stress, 4 of 6 diodes were damaged and soon after that, the battery was shorted through alternator’s stator windings burning them, measurements taken after the event showed a short circuit draining 210Amps from the battery with engine off, that is dangerous, extremely dangerous and it is a must to disconnect the battery as soon as possible in case of such event (I am afraid that a lot of people would not be able to do so and they can lose their cars at least), that is why some manufacturers fuse the alternator circuit with a maxi-fuse rated at maximum charging current plus 10%, on Crosswagon Q4 Alfa Romeo the alternator feeds from the starter which is unfused so the alternator is unfused too.

Here is a schematic of the alternator which contains a 3 phase generator, rectifier, regulator, all built in.

I tried to find the schematic of the alternator on the internet but I couldn’t, so here it is, it covers Alfa Romeo diesel 147/156 120A and 140A Denso models, this is also found in Opel Astra diesel models.
It may be a delta(considering it is a high power unit) not a star winding but anyway this doesn’t change the schematic by much.

Voltage regulator is Denso L9106A, solid state, no info on the internet available, but it is very reliable, it just survived a fire :).


Pictures with the disassembly of the free-wheel pulley and other parts:



Few considerations we need to have here, the quality of the old 140A stator is not achieved in the aftermarket replacement, but the goal is to have a rebuilt functional unit as good as it can be, with the lowest cost possible, the replacement stator side by side with the old one, it is rated for 120A, it should be enough for my Q4 as I always keep the electric loads under control, never using a lot of accessories immediately after engine start when the recovery is higher.

The winding of the new stator is a little bit different than the original, using a thick single wire, old one used a double wire winding.


All cleaned parts and new rectifier:


Bearings were in very good shape & good quality, added them some quality grease and everything is ready for assembly:


New stator in:



Now comes a very important part of the project, this makes the difference between a rebuild and a professional rebuild, the way that the rectifier is soldered to the stator wires, terminals are crimped and after that the wires were bent down to ensure a very good mechanical contact and in the end soldering was made with a high power soldering gun:



The brushes were replaced, notice the wear, new vs old brush:


The rebuilt unit:


Charging tests were successful, no charging light was present and the on board voltage is 14.4V, nice and good:



Installation of a maxi fuse rated at 130A will be considered in the near future, more automotive r&r projects will be available soon!

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June 3rd, 2015 at 8:40 pm

GWM Hover generator r&r

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This repair post is for a GWM Hover 2.4i(4G64 mitsubishi engine) SMD354804 generator.

The generator is made in china, it is 90 amp rated and it has been in service for 5 years(100.000km).
The problem is that the generator could no longer charge the battery and when you switch on the aircon and the low beam, voltage drops below 12 volts. With no load connected the generator manages to keep a steady 14.1 volt.
Another sign of malfunction is that the charging symbol(battery symbol) stays on for a few good seconds after start-up, this was the main reason to check the charging system performace.

Another reason for this check is that the winter is comming soon, you don’t want to do repairs in a -10 celsius day and you want your systems up’n’ready.

An overall system check was performed, battery check, electrical wiring and all connections have been checked.This confirmed that the generator is in a bad shape and needs a rebuild.

The generator on the workbench, first step was to make a sign on it(you can use a permanent marker) for us to know the exact position of the generator parts.
You can see the exposed rotor and the bearing, a good opportunity for a nice cleaning and we also added some lithium grease to that bearing, though the bearing sounded fine and no bearing play was observed.
You can see the opened bearing seal:


First sign of trouble was already present as one of the brushes fell down from its place showing some high temp melting damage:


After all tests, we were sure that the problem was given by the brush connection melting. The generator managed to keep the charging function at a lower rate using the spring of the bush as a connection. But not for long as the heat generated by this poor connection damaged the spring, affecting the overall performance of the device.

The rotor check:

Here you can see burned brush connection:

Everything was cleaned using compressed air and gasoline.We didn’t use gasoline for the rotor in order not to wash the grease in the bearings.

A new brush kit including new springs was used from BOSCH:

Brushes soldered in the old cleaned build-in regulator:

Here is the retainer pin used to hold the brushes not to damage them in the mounting process:


Regulator resoldered with a high power soldering tool:

Few other nice pictures:

Unit ready for another 100.000km service:

Charging test were successful, at idle speed(750rpm) 14.42 with no load, 14.39 with the low beam on, 14.22 with the high beam+fog lights and a nice 13.50v with ALL load ON (all lights on, aircon on, defrost on, seat heating on):

Let the winter be here!

In the end we must say that in our opinion the damage was possible because of the frequently jump starts given with the engine ON.If you want a healthy generator, it is better for you to do the jump start of another car with the engine OFF, this saves generator from heavy loads.
The quality of parts is not the very best in these chinese units but inadequate use leaded to early malfunction of the charging system.

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November 4th, 2013 at 7:50 pm

Lada Samara 1.5MPI r&r

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Russian car LADA(AUTOVAZ) SAMARA, can this be a subject for a serious repair&restore project?
Yes! Why?

Because this car developed in 1998(last generation, with mpi) had multipoint injection(from GM) with a single oxygen sensor and a catalytic converter(EURO2 standard) with carbon canister system and compared to romanian products it was a rocket, speaking in therms of technology used in it at that time.

It also has a nice bodyline, young and classic view( I read some time ago that the team who developed the car was very young and I could tell that before reading that article).

It is a very simple car, nothing complicated, no steering assist, no power windows, no central door lock.

The best points are : low mass, good non-interference powerful engine(51kw) with EURO2 standards, a very economic vehicle, maintained with very little money, something that it is hard to see nowadays.

Some photos of the car:

The beginning…

I purchased the car back in 2007. The car was good, excepting the wipers for the front lights. They were missing.
After 2 years of service the car suffered an accident, it was flooded. I thought “this is the end”, I rescued it and parked it for future repairs.

The first part of the restoration project included a paint job , overall cleaning, fluid changes, windshield replacement.

I would not insist in mechanical part of the project but there were some electric/electronic repairs that were performed. This is why this restoration is here at

At that point the car looked like this:

A new(from donor car) ECU ISFI-2S(GM) was purchased.This was a must to get the car started since the old ECU was in bad shape due to severe corrosion.Though the car started, it didn’t worked very well and soon the “check engine” light appeared.

This ECU has selfdiagnostics so it was preety easy to get the codes out by making a bridge on the OBD diagnostic socket.This is a list with the error blink codes specific to ISFI-2S ECU system:


The error code was 53 “CO adjust potentiometer failure”. This was a joke since such device was not present on our car, the car is equipped with an oxygen sensor to adjust mixture in closed loop operation.There was a mismatch, this new ECU was developed for non-export russian cars wich were not having an oxigen sensor but a potentiometer to adjust the mixture.

The EPROM in ECU was a wrong one and that needed to be changed in order to achieve the EURO2 standards, basically this was our focus in this r&r project, to achieve the best consumption/pollution numbers for this little beautiful car, as we do consider the environment.

I will use this opportunity to thank to Mr.Sim Oleg from who provided us the original ECU hex file for the EPROM in order to update our ECU calibration data.You know great people when you find them!
Their support was impressive, free, and without it, we could’t push forward this beautiful project – Lada Samara.

Here are some photos of the ECU and electronic programming procedure:



ECU updated, electrical wiring rechecked and a nice rebuild of the generator(80A) was all needed in order to proceed to the next stage:
road testing and gas analyser system check.

I will post some more pictures with the generator charging voltage(this is an older type 14v regulator system) , engine bay , cleaned&completely resoldered fuse box:




Some of the relays have been refurbished, some replaced as you can see in the fuse box picture. A spare fuse kit was included there.
Another fact is that we used a very limited budget as major components are from donor cars, as I already said, considering money and the environment.

With all the effort, car continued to act like crazy, showing up code 44(lean oxigen sensor) and other mixture related codes.Things were not good, something was missing, project was abandoned for a few months…

Further tests with the gas analyser showed a very rich mixture, high level of non-environment friendly chemichals at the tailpipe, car was a shame though it was running preety strong at that point.

Next step was a catalytic converter change(from a donor car-renault) and a “new” oxigen sensor(from another donor car-alfa romeo, BOSCH type).

This was also a nightmare change because the ECU dropped code 13 wich is “oxigen sensor failure”.

This is the old oxigen sensor AFS79 made by AC DELCO, a rare find these days, wich we replaced it with the newer BOSCH unit:

More investigation was necessary as it seemed the newer BOSCH sensor was not compatible with the GM ECU. That was partially true as the old style oxigen sensor used the ground (-) from the exhaust manifold.
The newer type needs a ground signal to be provided by the ECU , so all we did was to provide a ground signal wire to the ground signal wire of the BOSCH sensor.That was so easy!

The final result is a car who behaves as it should, a 15 year old Lada with perfect emissions, like the new car you’ll buy it tommorow.

In the end I will post the gas analyser log for our nice little project, Lada Samara 1500i :




More r&r projects in the “Automotive repair” section soon!


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October 25th, 2013 at 9:19 pm

Marantz CD-65 r&r

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This Marantz CD player is very similar to PHILIPS cd players from the same times. In fact Marantz used PHILIPS components, almost everything related to CD in the 80’s was made by PHILIPS.

As a plus Marantz added a digital output and a nice headphone stage with volume control, still keeping that fantastic classic look.


This unit uses CDM2/10 cd mechanism, I feel a little bad not having the mighty CDM1 wich is known as the best cd mechanism in the world.

It’s ok beacause CD-65 was released in mid 80’s so the “plastic era” was fully present.
Anyway it is a high quality product made in Belgium wich needed almost no service for 30 years.

Problems of the unit were: display flicker, random skipping, hard to make it work when first powered on, it needed 5 minutes of warm-up until I could listen to music.One day it decided not to read anything anymore so a repair was needed.
This cd player sounds so good that doesn’t deserve to die in my opinion.

First thing in mind was that the laser was almost dead but after a closer look, few replaced components, few hours of work, worked like in the first day.

First step was purchasing a service manual wich covers all schematics and the test mode settings.

Bringing the cd player in test mode showed that even the first step(focusing) couldn’t be performed, though laser beam was present.

I replaced all IC coupling capacitors. I was amazed how dead were the old caps, some had only 10% of their rated capacity.Age is age.

All boards were resoldered as much as it was possible after they were analysed.

After cleaning the lens, I recalibrated the laser power as it was a litlle off, this is a very good thing for the life of the laser.


The old wiring had problems, not all connectors , I found only one connector with problems and I recrimped original wires.


main motor lubed, unit ready for tests:


I would like to thank to Condor Audio from Israel for his high performance mods and repairs on Magnavox unit wich helped a lot in my repair project.You may check his beautiful website at

The cd player reads now the TOC(table of contents) of any cd very fast, searching is fast also.

Maybe in the future my cd player will receive some mods also: bypass the filters and muting circuits and OP amps replacement but i am happy for now using it the way it is.


Written by admin

August 2nd, 2013 at 6:26 pm

Posted in Marantz CD-65 r&r


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Written by admin

June 28th, 2013 at 2:07 pm

Posted in Automotive repairs

Kenwood KD-727 r&r

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Picture 359

This turntable was born in mid 80’s. You can also see it under the name “TRIO”.
It comes from the beginning of the plastic era, the one we still live in. As you can imagine this is not a high performance turntable but is a quality product made in Japan.

It uses a MC(moving coil) cartridge but since it came without it I installed a MM(moving magnet) AKAI-PC35 cartridge wich is a good cartridge.Now the turntable can be matched with a lot of audio amplifiers as most of them have PHONO stages dedicated to MM cartridges.

The big advantages this turntable offers are:
Low maintenance(direct drive), it is not at all sensitive to transport and can handle a lot of abuse, all this comes together with a decent sound.

Defects were:
-missing cartridge, installed akai PC-33 with RS-33 stylus
-old belt for arm transport, belt was replaced.
-worn arm transport rail rubber suspension, replaced with silicon ones.
-you could hear in the speakers when listening to music(slow passages) the servo mechanism coming in from time to time, this was solved by using a siliconic grease for arm transport.

Picture 365

Another picture with this turntable

Written by admin

June 27th, 2013 at 7:34 pm

Posted in Kenwood KD-727r&r