Disco 2 Webasto Fuel Burning Heater install

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backinblack said:
@biketeacherdave Pin 1 goes to the Telestart remote module to receive a 12v start when the remote is pressed. Pin 2 is the WBUS. Pin 6 is the fuel pump

EDIT:- This is part of the diagnostic kit I used to talk to mine
https://fnltd.co.uk/shop/diagnostic-loom-lead-for-webasto-thermotop-c-lr-rr-bmw-p78.html
Click to expand...
Thanks backinblack. My car a 2003 is canbus only NO w-bus. I will be doing a full pin out diag on the car before fitting. I have a thermo top C fbh which is analogue only. My research has found an online circuit diagrame
https://www.elforum.info/topic/66911-problema-webasto-thermo-top-zc/
Which shows which pins do what. Pin 1 is clock so could be the switched 12v for start up but the famous utube has people using pin2 as a switched voltage.

Will see what the car is using as I should have all the plugs already in the loom. Whatever iv got I'm going to connect it all up on the bench 1st if possible I want it to work with the built in park heating function and on a remote. As I never use the car at the same time of day the remote function is a better solution but wont turn on the cars ventilation system. I do have all the pipework and change over valve for cabin heat only but again warming the engine and heater matrix at the same time is my real goal.

A right result will be to find both pins 1 and pin 2 both activate the fbh meaning the car using pin 1 and my remote using pin 2.
 
@biketeacherdave I hope you are right with the 2003 non canbus. I still haven't got my head round what was changed in the different years of development.
From the testing I have done on the 5 FBH's I have collected one is a 2002, one is a 2005, one is a 2007, all of which including the 2002 can be diagnosed with the WTT WBUS connection on pin 2. I haven't come across anything that says you need this for a 2003, this for a 2005 etc so assumed there was/is no difference. I have read that lots of car makers use the Thermo top C with their own pcb though.
That's not to say a 2003 will need pin 2 on WBUS but yes you will find out when you bench test it, but please let us know for my own sanity at least :D

This is the unit I used for the remote to pin 1 if you're looking for ideas, only issue is the buttons on the remote stand a bit proud so I 3D printed a surround to stop accidental presses. More than happy to send you some if that's the way you go.

Amazon product

upload_2021-1-18_22-48-20.png
 
Well after making a loom, sorting out a 12v switching remote to activate the fbh........the fbh circuit board is dead.
Iv even made a diag lead to use with the webasto test software to check it for faults but even that wont read it. Good news is the breaker I bought it from is sending me another unit.
So all.on hold for now
 
I have had both Eber and Webby heaters fry their circuit boards.
Back then you could only get genune, and of course they cost more than the heater was worth!
 
I currently have 5 thermo top C's and there is only 1 that I can't connect to, don't know if it's just knackered or off something with different pinouts but now I have 2 working ones I can't be ars3d messing with it.
The 5th one is on the L322

upload_2021-1-28_20-7-34.png
 
biketeacherdave said:
Connected to pin 2, as you say pin 1 is the 12volt start up. I'm going to look at my settings on the coms port to see what's going on there.
As far as I can tell even if the boards fried i should still be able to connect to it for diag
Click to expand...

Some of mine have faults but yes apart from 1 I can fire up various components.

If the com port is wrong IMO the software will show a com port error. Did you select Thermo top c/z BMW since you got the L322 webasto



upload_2021-1-28_20-49-1.png
 
backinblack said:
has it worked?
Click to expand...
Yep I can now connect and talk to and test the fbh, but as you can see from the screen shot a lot of the icons are not lit/working at the top. I cannot prime the pump or start it using the webasto software.
The circuit board I have should fire up with 12v applied to pin 1. People are selling these boards as such it's a throw back to the BMW tele start remote system.
20210129_213023.jpg

When I connect my 12v to pin 1 the ms indicator lites up. When I try the component test everything switches on 1 at a time with no faults reported.
Will get a can of freeze spray on order as I'm out then I can spray the thermistor on the board to see if that's stopping it but I should still be able to activate the fbh with the software.
 
I don't get an option to fire it up either, I still don't think it's possible to fire it up unless it's connected to the car but I could be wrong. I don't think Pin 1 is a throwback IMO it's the only way to fire it up remotely as the car is asleep so can't do it for you, this is what I was told by the chap I bought the test leads from. If you put a scope on pin 2 you can see the FBH signaling the car and waiting for a response when you put 12v on pin 1.
Have you got a fuel pump connected?
 
Is the FBH fitted to the car or on the bench?
If it's on the bench have you got the fuel pump earth connected to the main earth on the FBH?
 
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