Battery drain still going on

[A80Avant]

Question:

I still get a battery to die on me after inactivity of the car for little over 2 weeks.

Put in a new battery varta silver and have the same issue.

Already changed:
Dodgy alternator.
Battery cable on the rs2 with a new original unit from audi tradition

So far checked battery voltage sitting at 12.8v after an overnight stay without the alarm on.

14.4v with the engine running

And 0.06 drain (20mA) setting

May I ask if the above sound wrong and if so I'll start pulling fuses to see where that drain is coming from...

[driftin jo]

0.06 is 60ma ( milliamp), is it this at rest ?
So in 2 weeks you loose 20 amp hours of charge, that's a lot!
It's bit on the high side 60ma, something is not right.
It should be closer to 20ma, which will cost you 6.72 amp hours of charge over 2 weeks, not too bad if you have a ~75 amp hour battery.
It should be noted also, when it is cold, your battery has a considerable loss in amp hours available, so any drain is also magnified.

Also it has to be said that if your charger is a cheep crude type it may well be destroying your battery.

Other things to consider are the fact that a car battery is not supposed to ever be drained more than ~10%. every complete discharge and recharge you will loose 5-7 % of it's capacity.

[piotr]

0.06 Amp its alot.anything more then 0.02Amp and i would start looking for drain.when i tested my car it drop to 0.00.

[martinws]

I would start testing fuses to see which one is causing the drain. Attach the ammeter at the battery and you will see the 60ma as mentioned, now start pulling fuses until you find the one with the most current going through it and look at components from there.

[UrS4boy]

B3/B4 and C4 Electric Window and Sunroof Control Module Info

On a C4 UrS, that kind of battery drain almost always ends up to be a bad trace (broken solder joint) in the electric window and sunroof control module, 441959257B, aka "329" in the C4 driver's side kick panel:

http://forums.quattroworld.com/s4s6/msgs/154280.phtml

On a B3/B4, this module seems to be 441959257D, in positions 5&6 on the S2/RS2 relay panel. Probably labelled "327", as shown below.

[A80Avant]

Thanks for all that guys. I think i have a spare of that relay as well. I may give that a go. Will report back

[EspenW]

Yep, I resoldered a broken joint in that relay a few years back.
Symptom was that the driver side window got stuck in the half open position.
Got home, searched the forum archive, found the solution, pulled the relay and fixed it.

[newsh]

On a C4 UrS, that kind of battery drain almost always ends up to be a bad trace (broken solder joint) in the electric window and sunroof control module, 441959257B, aka "329" in the C4 driver's side kick panel:

That is really good info, I've had a mystery current drain (I nearly wrote discharge ) for a long time, sometimes the battery lasts ages with the car parked up, sometimes it struggles to start after being left a few days. I shall have a look at that relay.

[UrS4boy]

Yep, I resoldered a broken joint in that relay a few years back.

I used to call them relays too but they are not. No mechanical bits inside. *ALL* electronics, including chips, etc. They are control modules. Sorry.

But for example, there are still lots of real relays with solenoids and contact points in our cars. They are easier to diagnose.

Control Module (324 in this case - after-run pump and fan):



Servotronic control module:



Generic Relay

[rj scotty]

Tested mine for you

Locked and alarmed I get this



38.2mA

I pulled all the fuses in turn and it did not drop.
My battery drains after about 2 weeks of no use.

My solution is a smart charger

cheers

[A80Avant]

So with 40 ma it still drains in 2 weeks. That's no good. I have to get it even lower than that then!

[newsh]

http://www.ebay.co.uk/sch/i.html?_fr...witch&_sacat=0

[rj scotty]

http://www.ebay.co.uk/sch/i.html?_fr...witch&_sacat=0

Crude but 100% effective

[driftin jo]

If you don't use your car daily get one of these :

http://www.ebay.co.uk/itm/Accumate-O...item3a9b7507a3

[A80Avant]

To me all these solutions are bandages to the problem though. Modern cars don't have these issues, right?