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Archive for June, 2015

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