LantzQ7

I have a 2007 Q7 3.0TDi.

I live in the cold in Norway, so I would lke my Aux Heater (webasto) to work Unfortunately, it doesn't help much. This is what I've got:

Starts up on remote.
Can here fresh air fan running at the start.
Shuts down after a couple of minutes
No heat in motor, and no heat in the coupe.
The fan in the coupe doesn't even start.
In VCDS I can find a temperature that I read to 80deg C at some point proving that it did indeed fire up.

This seem to me to point to the circulation pump, but I suppose there should be a fault code in VCDS if it weren't running, and consequently shut down due to overheating? There re no fault codes in VCDS.....

Any ideas how to go about this?

smith2010Q7

Here is some testing and inspection of your heater Aux. Hope you able to find the problem.

Q7 Testing and Inspection Aux heater.pdf

LantzQ7

Thanks Smith, I believe this is for some kind of electrical heater though.
Mine is the fuel driven one. Your program wouldn't happen to have some nice information on that too?

smith2010Q7

Will research, unless are you talking about just a reg heater core?

LantzQ7

no.
It is a seperate diesel unit (Webasto). I burns diesel to get the motor warm mainly, but when switched on manually it's supposed to heat the coupe as well.

Edd W

If it is set to Auto mode, does it run and keep running when the engine is cold from start up?

smith2010Q7

WOW now i understand, The coldest in Wyoming we every get is -20, but never had this great heater to warm everything up.
Ok I found this thread about 10 pages hopes it gets you in the right directions for your heater. i was looking at a week battery or might have to reprogram your system.

Stay warm!!

parking /auxiliary heater | Audi Forum

Jonte75

Hi,
I live in the cold Sweden and I use the heater every day this time a year!! Like Edd W wrote, do you know if the heater is working in normal auto mode? Have you had problem the get the interior warm in a cold day in normal driving? I have a -12 model sold as new in Sweden and the standard program is set only to warm up the interior when you start the heater via remote. But you can change via VCDS to warm up the engine also but the heater need quite long time then. Does the rest of the acc working without fault codes? Because if the heater think the coupe is warm enough it will shut down...

NorthernQ7

Same car, same country, same problem here. Heater works fine as a supplemental heater, I can hear the fuel pump ticking happily away and it gets hot quite fast when the engine is running. Does your heater do this (when less than +10degC outside as that is the default temperature limit on this car) ?

My problem is similar in that when I use the remote to fire it up, it fires up but shuts down after a few minutes. This only happens if it's very cold outside - I believe the heater has a glow plug / flame sensor that might need cleaning or replacement - if it doesn't fire properly when cold.

Is your battery up to speed? I recently swapped mine for a 110Ah model and it helped a lot since we do mostly short trips to the kindergarten these days, it gets low on power pretty fast - down to about 12.4-12.5v idle voltage.