Somebody please help (battery drain)

[mrlinderley]

Hi everyone
I have a strange problem with my 2001 2.5 TDI Quattro A4. After 2 days of my car being stood the battery is flat. I ve noticed that when I leave the car either locked or unlocked for about a minute the backlight for the hazard warning light goes on and off about every 15 secs as does the light on the switch for locking the rear windows. I ve used an ammeter to test the current draw and it reads 1 amp when the lights come on and zero when off so this is obviously the problem. I ve removed the bulbs and the draw is still the same so something else is being activated. I ve gone through all the fuses in side panel and none of them make any difference (is there another fuse box somewhere?) I ve cleaned all the contacts in the electrical box under the passenger side footwell and it seems like there is no water ingress. I don’t know what else to check, could it be a faulty relay (clicking can be heard in the car as the lights go on and off) and if so which one controls these 2 items. I really hope someone can help as I need to sell it asap. Sorry for the long message.

[Teflon]

I know I might be teaching my Granny to suck eggs here, but how old is the battery?

I had a very similar problem but battery and alternator were both confirmed as perfect when the RAC came out to my dead car. Spent 4 weeks chasing down every tenth of an amp of current drain, without success. Seventy quid's worth of new Bosch battery later the problem was solved, never to raise its ugly head again.

[bora(ing) nick]

I know I might be teaching my Granny to suck eggs here, but how old is the battery?

I had a very similar problem but battery and alternator were both confirmed as perfect when the RAC came out to my dead car. Spent 4 weeks chasing down every tenth of an amp of current drain, without success. Seventy quid's worth of new Bosch battery later the problem was solved, never to raise its ugly head again.

Hey Ronnie....



To the OP

I don't think it's the battery... i think you have a cable fault. Are the lights flashing as you would expect the alarm indicator to flash?

The comfort module (under the drivers seat i believe) when wet can cause all sorts of strange problems.

AFAIK it's not normal for the lights to flash as you described

An ECU scan may throw up the cause??? (circa £30 from a good auto electrician)

Good Luck

Nick

[mrlinderley]

Thanks for the replies

The battery is only 6 months old so I don't think its that. I had a look at the comfort module (under passenger side left on mine unless i found the wrong thing) and cleaned all the contacts and there was no sign of water either.

My thoughts now are that it could be the alarm or immoboliser. The handbook states that the indicators should flash when i set the alarm with the remote but they don't. Also the led on the door is meant to flash rapidly for 30 secs then flash slowly. mine flashes slowly from the start but when the hazard backlight comes on inside the led flashes again. I could be way off the mark here though because the problem also happens when i havn't locked the car and therefore the alarm isn't armed.

Is there anyway or disabling the alarm and immoboliser to test this theory?(fuse etc)

One more thing, as hard as i try i can't set the alarm off. Is there a sure way of doing this just to see if it is actually armed?

[mrlinderley]

One other thing I ve noticed is that i can't enable the 2 switches in the drivers doors (ultrasonic and tow away) The leds are on. Any clues anyone, could it still be a convience module problem?

[charliebucket]

Hi, i got very similar problems in my 2004 S4. battery has been draining overnight. Audi tested battery, that was ok, then thought it was the Bose amp, so disconnected that. 2 days later, flat battery again. So, back to square one. ALSO, just noticed thisevening, that the hazard switch is constantly illuminated wether the alarm is on or not. going back to audi tomorrow, but as they dont seem to know what the problem is, i was hoping someone here might.

[kite]

Hi, i got very similar problems in my 2004 S4. battery has been draining overnight. Audi tested battery, that was ok, then thought it was the Bose amp, so disconnected that. 2 days later, flat battery again. So, back to square one. ALSO, just noticed thisevening, that the hazard switch is constantly illuminated wether the alarm is on or not. going back to audi tomorrow, but as they dont seem to know what the problem is, i was hoping someone here might.

the hazard switch should go off after around 30mins.

[danclyon]

the hazard switch should go off after around 30mins.

As a side note - why does it stay on? I can't see any real purpose.....for what it's worth they might as well have fitted a backlit Audi logo on the dashboard :-)



Dan.

[charliebucket]

the hazard switch should go off after around 30mins.

maybe it should, however, mine does not. it used to go off about 20 secs after locking, but now just stays on constantly, along with the backlight for the little switch that enables the headlamps to stay on for a little while to light your driveway!. ( Im sure its got a shorter name...)
BTW. been back to Audi, they are still sure its the Bose amp at fault cos, as they said, it regestered such a big drain that it couldnt be anything else. also, that the battery must be weak even though it tested ok.
We shall see what happens this weekend....

[mrlinderley]

problem solved. turned out to be the steering column ecu. A very helpful guy called jamie at Audi Sport in Great Harwood, Lancashire sorted it. £250 parts and labour. No more battery drain and my hazard warning light now goes off. Result!!!!!!!