CAN bus auxiliary heater in the Skoda Fabia 1

Hello community.

I installed an Eberspacher auxiliary heater from a 2008 Audi into my 2006 Fabia.
Unfortunately, it won't start. The error message indicates that there is not enough fuel in the tank.
I can only read the heating system's data if I connect it directly to the diagnostic port.
If I connect it to the engine or comfort CAN bus, VCDS cannot access it.

Help

And thank you in advance .

Hello,

How is the auxiliary heating control unit accessed, via K-line or CAN bus?
Integrating the latter into a vehicle for which the heating system is not intended would likely be difficult. Has the gateway for the auxiliary heater been configured?

If the heating system is controllable via a K-line connection, I wouldn't waste time trying different things; just connect the wire directly to pin 15 of the diagnostic connector in the car. This pin is usually the L-line or K2-line, but it's not used in your Fabia.

Regarding the heating system error message: It would be helpful to post the exact error message. If there is a fuel shortage, check the correct connection; the fuel return line back to the tank should NOT be used for this purpose!

Best regards, Rainer.

The heating system only uses CAN bus technology.
And she also gets her fuel level information from that source.
I think this will be the main problem.
Das Gateway ist nicht konfiguriert. Ist ein guter Hinweis. Aber wie?
I'll read the exact message again. I only wrote it from memory, more or less.

Hello,

You can try to integrate the control units for the auxiliary heater into the gateway (address 19) via "coding."

From a purely logical standpoint, the control unit should be integrated into the "Comfort-CAN" system and must take into account CAN-H and CAN-L, meaning that they should not be swapped.

Overall, I estimate the probability that everything will work as desired, given the quite different vehicles involved, to be rather low.

Best regards, Rainer.

I'm not anymore either .
I still have the short encoding in my gateway.
According to the wiring diagram, the heating system is connected to the chassis's CAN bus.
Now, perhaps we could simulate the gasoline signal using an AVR microcontroller.
But unfortunately, my skills aren't sufficient for that.
Soldering and writing small programs are no problem for me. However, I haven't yet worked with CAN protocols.

Perhaps there's a standard control unit available for your auxiliary heater that supports diagnostics via the K-line, and you could connect it like a regular aftermarket heating system.

That would certainly be the easiest solution.

Best regards, Rainer.

Simplicity is key.
But then I would have to buy one for a lot of money.