Doesn't it only come on when actually cold and there is demand for heat from the a/c, as in winter?

IIRC aux heater only becomes active when ambient temp gets down to 6 degrees or around that .

If you feel that it is taking to long to get warm ,like already said it could be a thermostat issue ...opening to soon or not fully closing allowing partial flow through the radiator.

As a bit of a ‘bog ‘ just for *testing purposes* if you slip some cardboard in front of the radiator ( like ya used to see in’th olden days ...Ray will know ! ) just to stop air flow to it ....if it then gets warm much quicker you know your on the correct track .

There is a few other things that can cause slow warm up ....any ideas technical guys ?? Just out of interest so

Cheers mate

Chhe
Cheeky booger Lee.
I'm not doing anything today so I might bring the boys round to have a word :D


I used to be in charge of the honorable ancient blowlamp for warming up Boadicea's chariot wheel knives. It made the blood flow easier after cutting.

https://audi.7zap.com/en/rdw/audi+a8.../1/121-121039/
Part 6 on this diagram is a common failure that results in cool running/slow warmup due to bypassing the main thermostat and continually circulating the radiator and autobox cooler.
They are about £15 new on ebay.

I have been reading on that fix - do you have any info on replacement of this part?

Thanks for your help.