I think the glovebox torch may also run off the light fuse - have you tried removing it in case it's shorting out through old age?

My drain (which I still have to a degree) is down to the radio / satnav modules - fuse 57 iirc. Very common it seems.

You are allowing the car to go to sleep for the full ~16 mins when you test yes? I had to fool boot and door switches to make it work correctly.

Simon

 

Hi.

One answer would be to look at a potentially faulty GM3 module as both fuses relate to it, and it is the module responsible for putting systems to sleep. There are other related parts though, such as relay K72. If that relay doesn't release then it leaves all the seat and steering column modules on. Try pulling fuse 13 instead of 4 (or just pull the relay) to see if that reduces the current drain. There are a host of other loads that should shut down when the lights go off. Do a search online for "BMWGM5 E39 VA signal" for some useful info. Hope this helps a bit.

 

Does your ac / heater fan run variable from time to time? The regulator for that fan has been known to go bad and cause a parasitic draw.

 

I think this is the issue I am having with my e39 - does anyone know the fix for thi issue?

 

Hi

Thanks for your replies.

I have unplugged the torch Simon and it's still happening but I wasn't actually letting the car go to sleep properly. General current draw seems to drop drastically after a couple of minutes but I realised that isn't going to sleep so I retested after about 16 minutes or so and I was getting around 40mA with fuse 4 pulled therefore leading me to believe that it's perhaps only circuit 4 that is causing the problem.
I will retest and see what I get.

Can you point me in the right direction to find relay K72 please THE39M5? Is it behind the glove box?

The ac/heater doesn't run variably that I have noticed. Is the regulator you refer to called a hedgehog? I think it's the unit that is basically a big resister with spikes on it that lives behind front heater outlet. If so, that was replaced in October last year so it would be unlikely to be that I would have thought.

I'll keep digging but thanks again guys.

 

Yes behind the glove box

Picture & amperage & description of every single fuse & relay in the BMW E39 - Bimmerfest - BMW Forums

 

You are reading from the fuse chart but that does not really tell you what the fuse does or how the system works. You need to look a the wiring diagrams, so I did for you. Fuse 4 is the general module, those things you list come out of the GM but really that fuse is powering part of the GM so getting it repaired would likely solve your problem. There are a few threads on where to get them repaired.

 

Take a look here:

http://www.bmwgm5.com/bmwgm5/Images/E39/E39_VA.htm

Hopefully I have inserted the link properly. These are parts of the WDS wiring diagrams for the circuits that the GM3 module controls the power to from fuse 4. They should all go off, including relay K72. There is an image of the relay in both left and right hand drive cars, I believe you can get to it by taking out the storage bin to the right of the steering column. A relatively small leakage current could hold the solid state relay on when other things appear to be dead. It most likely still points to the issue being in the GM3 itself. The website also shows where the module is (up the back of the glovebox, accessed from the back of the footwell). There are a few UK repair shops now for these modules, a quick search for E39 GM3 repair should get you there.

 

Im having battery drain issues as well from my 2000 M5.

This link has tons of information, I would start here.

Detailed step by step diagnostic DIY ... dead battery ... parasitic current drain - Bimmerfest - BMW Forums

Not trying to hijack but since Im having issues and havent found the solution ill ask here.

My car is drawing approximately 3amps in sleep mode. My alternator is not charging the battery as it should. The alternator has nothing to do with my battery drain does it? Im verifying that I have two separate issues correct?

 

Hi S30. What diagnostic work have you done so far? How do you know the alternator is not charging as it should? Let us know what you have tried so far so there is a little more to go on. The alternator is connected directly to the battery so it is possible it can cause a drain. If it is causing a drain then it would certainly be faulty and likely wouldn't charge correctly either.


Just to clarify, the location of several relays on right hand drive cars (such as K72) is different to left hand drive ones.

 

Thank you for responding and clarifying.

I tested it again this morning, the battery was reading 12.8V I turned on the head lights to get rid of the load and only the side lights came on, is that normal?

Anyways with the car running, I saw 12.1V with only the radio on (How do I turn off the radio? I pushed the knob in and it doesnt turn off? I think im onto something here)

Car running, with the radio, AC on high, lights and fogs, 11.9V

Car running after going to the parts store and back (30min) 11.5V

11.9V with the car off after approximately 30 min.

I also have the red battery symbol and I'm getting infamous alternator belt whine.

I tested the battery and alternator with the following results:

I told him 850 CCA, I guess he entered his assumption before asking. If he rated my battery at 600 CCA, does that effect the results? How can my car start if it only measured 78 CCA?

I believe Im having both a draining problem and charging problem. My alternator is not charing the battery and my car at anytime is drawing 3amps in sleep mode.

My main question is it possible for my alternator to cause a parasitic drain? I'm under the impression the alternator only causes change in current when the vehicle is running.

I got the car a month ago so all this is new to me sorry.

 

I'm guessing you are quite DIY capable as you have been measuring the current? If you have the red battery symbol and the test showed inadequate charging then check the belt is on, in good condition and correctly tight. If the alternator is spinning as it should then perhaps one last thing would be to charge the battery off the vehicle to see if it is okay. If the battery charges okay and holds its charge while not in use then it all points to the alternator. A bad alternator could cause a parasitic drain, this might cure all your issues.

I can't comment on what the battery tester would report if it was given the wrong CCA. I agree the result looks wrong as you are still able to start the car.

Low battery volts causes a host of electrical problems such as the audio and nav systems not responding as expected. Get your battery properly charging and you will likely find other things are resolved.

 

Thanks again for the replies.

I would appear I was being a bit of a numpty and not actually giving the car enough time to go to sleep.
I have retested while it's properly asleep and it appears to be drawing about 40mA which is correct so actually no parasitic draw.
I have tested the alternator and that is charging the battery fine so that only leaves the battery.
Evidently, as I don't use the car day to day (and when used it's usually for short journey's), the battery is not being kept as charged as it should be and therefore, after being discharged to the point where it won't crank the car over, it is now not able to recover as it should.
The battery is 2 years old and has a 4 year warranty but I am not confident that, when tested, it will have any sort of manufacturing defect, instead incorrect care of the battery.

So I think it is solved.

Thanks again and apologies for any wasting of your time.

 

Hey S30

I'm no expert but I'll certainly say it as I see it. Happy to be corrected by anybody though.

Strange that you were only getting 12.1v with the car running and the radio on when you were getting 12.8v with the engine off.
It should be the other way round. I would have thought you should be getting more like 13.5v with the engine at idle increasing as you blip the throttle.
It appears that the alternator might be drawing current rather than charging the battery.
Also, the main headlights wouldn't come on if the ignition isn't on, just the side lights.

 

It is not really the battery but now might be. Likely the same thing happened to the other poster. The battery is charged but the alt which is controlled by the DME not just the voltage regulator. They do this for efficiency and you know German. Lets over complicate some thing that works fine. Without all the detail on different ways it does things, I have typed all that too many times.
One dumb thing it does is evaluate the battery at startup and decide the condition of the battery and will only charge it at a certain rate based on what it decided.

What that means is these cars will not fully charge a dead battery. They seem to go to 12.7 volts or 70% but no more this kills the battery in the long term.
If you every have a dead or weak battery you need to charge it on another charger first then the car will keep it full. Not a trickle charger they cannot fully charge a battery(volts to low) and if they could it would take 20 -30 days (amps or watts).

 

Thanks for the help guys

I fully charged the battery and watched it over a couple of days. Charged to 12.6V, overnight 12.4V and has remained at 12.3V for days.

Got a new used alternator and volts went to 13.7V running and 13.1V under load.

Now just a reminder, I was drawing about 3.3amps in sleep mode and it went down substantially to .13amps.

Fuse 56 (nav, radio, on board monitor, cd changer) lowered it .10amps to .03amps

Fuse 11 (servotronic) lowered it .01amps to .12amps.

I tried it again with both fuses removed and confirmed .01amps.


Took it out on the road and filled her up for the first time. When I brought it back I noticed my front passenger door wont unlock (inside and out).

At first I was thinking ok door actuator but the more I read on fuse 56 has me looking into the GM III module which controls the door switches amongst others. Do you think I should start there since its fairly inexpensive?

Thoughts?

 

also check this... E39 Electrical Problems Traced to Trunk Lid Harness Wire Chafing (DIY Diagnostic) - Bimmerfest - BMW Forums

 

I had the same happen with my M when I bought it. Turned out it was the interior cell phone draining the battery.