Q3 Q3 parasitic battery drain, any electrical gurus?

[bagger_12]

Hi all I’m having some bother with my Q3. It has a 2.1A drain on the battery. By removing fuses I narrowed it down to the climate control unit and then confirmed it by unplugging the unit itself with the fuse refitted giving me a perfect 25mA drain. The climate control unit has 4 plugs on the back so I’ve also narrowed it down to 1 of the 4 plugs by plugging them back in 1x1 until the drain reappeared. The plug in question has 7 wires, 2 of which go to the multifunction control module. Is the multifunction control module Audis terminology for the BCM (body control module)? Has anyone come across an issue like this before? I was hoping the 7 wires on the problem plug would just go to the flap motors making it easy to diagnose but the fact they go to a multifunctional module that probably controls half the car complicates matters.

 

[NHN]

Which year?

Which colour plug is the one in question & how many pins does that plug cater for in total, even if not all used?

 

[bagger_12]

2013 and it’s the brown plug (C) not sure how many pins the plug is but it only has 7 used pins in it. They go off to air purity sensors, vent temp sensors and of corse the multifunction module

 

[bagger_12]

Just looked at the picture it’s a 16 pin plug with 7 in use.

 

[NHN]

Whats the actual wire colour as elsawin isnt denoting connector colours unfortunately.

Can you show me a pic of the actual connector & each pin is number marked in the plastic, maybe with a torch tou can see it, the out part slides of the inner, both plastic parts usually have pin numbers embossed.

 

[bagger_12]

Whats the actual wire colour as elsawin isnt denoting connector colours unfortunately.

Can you show me a pic of the actual connector & each pin is number marked in the plastic, maybe with a torch tou can see it, the out part slides of the inner, both plastic parts usually have pin numbers embossed.

I’m not with the car right now but I have a picture of the wires and also my notes. Hope this helps.
The D at the top is my mistake and should have been a C

 

[NHN]

Orange brown is a bus wire mate, so if disconnecting that kills the draw, then a network signal is keeping the cluster on, thing is, is it a climate unit fault or another network connected module at fault.

 

[bagger_12]

Makes sense! Yes that is the thing I guess Il try a second hand climate unit then go from there

 

[bagger_12]

Orange brown is a bus wire mate, so if disconnecting that kills the draw, then a network signal is keeping the cluster on, thing is, is it a climate unit fault or another network connected module at fault.

Just borrowed a climate unit from a friends A3 and it’s cured the drain. Any idea if it might be repairable? Buying second hand would be a gamble considering they clearly go wrong.

 

[NHN]

Just buy a 2nd user one & test, ebay then if faulty return.