Webasto won't fire, fuel or communication?
 

Noticed lately that the aux heater doesn't work and give error code in VCDS with "No Flame".

Totally get 3 errors for the Aux Heater:
01406 - No Flame
01336 - Company Data Bus for Comfort System - No signal/communication
01407 - Flame Extinguished

And one for the CAN Gateway
01207 Control Module for Auxiliary Heater - No Signal/Communication

I wonder if the 01336 and 01207 are related to one another, and are triggered because of the Webasto goes into lock and need to be reset/opened after "No Flame" error?

I've taken the Webasto out and apart, and everything looks fine. The glow plug measures 0,5 ohm, with the probes shortened 0,2 ohm, so should give about 0,3 something for the glow plug alone. From what I understand that should be okay?

Tried to test run the Webasto from the VCDS, while not connecting the fuel line, and everything seems to start and run as it should apart from that it obviously didn't fire. No diesel came from the fuel line, so I expect maybe the dosing pump to be faulty?

Question is, should I follow the communication errors, or are those related to not firing, or should I check the dosing pump?

The last question is, where is the dosing pump located? I've searched high and low online but can't find any information about it.

The car is a A8 2006 3.0TDI and the Webasto doesn't have a timer or remote.

Dosing pump should be under the car near the fuel tank, it should click audibly when working, you should be able to run dosing pump seperately from vcds to check

Thanks, I also think it is in the rear somewhere. Any idea of where in vcds I can test run only the dosing pump?

I don't know where in VCDS exactly, but there must be an option - probably under output tests in aux. heat
I have used the function in webasto's own thermo test software - there was a function called fuel line prime which ran the dosing pump

I'm sure you can enable a pair of timers in the HVAC section of the instruments using VCDS, just a matter of turning them on using the coding, at leeast if you've got no remote then that may be better than nothing

Not sure what Webasto heater is in the 8 but the cab heater type i have is an Airtop 5000. You can hear the fuel pump clicking when it's running. If it's not been run for a while it can take a few fire ups for it to actually start up. There is a filter in line too somewhere i would have thought. If it had the Webasto thermostat it flashes a fault code that relates to the problem. I downloaded a load of stuff for it from Butlertechnik, service, parts, fitting instructions ect

The full name is Webasto Thermo Top C.

This might help along with the 8 fitting guide

my A8 has one of these fitted
are they standard
and what does it do and when ?