Possible fault in Instrumentation Control Cluster

[HeatherG]

Hi there

 

I'm new to this forum, and I have a problem (Audi A3 8P 2010).

It has a new battery, just six months old, and over the past few weeks it's been running right down while the car is parked up.  It holds its charge when the positive terminal is disconnected, so I'm looking for a fault in the car. 

With the battery fully charged, and the ignition off, I've checked for current across whatever fuses in the engine compartment that I can access while the fuse is in place (all the smaller fuses up to 20-30A - the thinking (possibly false?) that there should be no current flowing while the car is switched off.  I'm getting a current across the 5A fuse at position F6, and a bit of a search on Google brings me to the diagram corresponding to the layour of my fuse box.  F6 is the Instrumentation Control Module.

My initial questions are:  first, would a current across this fuse indicate a fault in the Instrumentation Control Module;  and second, if so, then what - is it possible to buy a new module and just plug it in (wherever it's located, which I don't know), and would that be very expensive or is there another option?  I live in a pretty remote place, so that getting the car to an Audi service place and leaving it there would be difficult for me.

I'm by no means a car expert, as you can probably tell, but I'm hoping someone might be able to advise.  The next step, I'm thinking, might be to remove that fuse and see whether the battery still discharges when the car is sitting and not switched on;  the battery won't be fully charged till tomorrow, so in the meantime I'm trying to explore whether I'm on the right  track or not.  I should add that as far as I know the various instrument functions are ok, but again I can't confirm that till the battery is back connected up.

Thanks in advance

 

Heather

[Rybrook]

There is a consumer delay of about 15-20 minutes, from when you turn off the ignition or unlock the doors.

You can see this by either opening the boot and watching the light turn off or removing the key after a journey and waiting for the interior cabin lights to turn off.

I have a broken light in the glove box, the switch broke and the lamp eventually burnt out, this caused a parasitic drain till it broke.

Only noticed when I swapped the concert radio for a new unit.

[Steve Q]

Instrument cluster issues are well documented. I'd recommend getting an auto electrician to take a look at the power drain. 

[HeatherG]

Rybrook, thanks very much for that info.  Actually, though, the car is sitting unlocked and no one entering it and nothing switched on.  Battery still draining. This morning, w battery fully charged and reconnected, and at about 12.7V, that fuse is still showing current.  Now, I've taken out the fuse and I'm going to check through the day to see whether the battery remains fully charged.  Before disconnecting, I did enter the car and started it. When running, it's now showing a wee steering wheel symbol; the handbook says that's power steering, but the listing of fuses says clearly that F6 (5A fuse) is Instrument Cluster. I suspect that the power steering bulb being on may be an artifact of a failure in the instrument cluster module.  Do you think that might be the case?

[HeatherG]

1 hour ago, Steve Q said:

Instrument cluster issues are well documented. I'd recommend getting an auto electrician to take a look at the power drain. 

Steve, thanks very much for that.  Yes, that'll be our next step. It's a nuisance, though, cos we're so remote, but I'm going to have to do that, I guess.

Thanks again. I'm no expert, though I can use a multi-meter and not too bad at figuring stuff out. But I think I've gone as far as I can.  Thanks again.

[daveyboy1967]

On 4/24/2025 at 2:45 PM, HeatherG said:

The next step, I'm thinking, might be to remove that fuse and see whether the battery still discharges when the car is sitting and not switched on

This would be a good first step, it would at least let you know if you're heading in the right direction or just chasing shadows. Parasitic drains can be really hard to trace but I've read a couple of good guides that helped me in the past, if I can find them again I'll post the links here, good luck.