4 to 17 amp drain, e39 02
4 to 17 amp drain, e39 02
Author
Discussion

billy5

Original Poster:

235 posts

235 months

Thursday 9th August 2007
quotequote all
hiya all, my daughter has a problem with
a power drain from battery,
the rac have told her its between 4 and 17 amps
the alternator is ok,
theres been probs with the hazzards coming on wen the car
is stationary, and locked.
is the alarm too sensitive,,
if so can it be adgusted, could this be the problem.
also, wen you turn the key off with air con on,
the fan will run on for 4 to 5 secs,
any one had probs with aux ventilation settings[timer]
any thoughts welcomed, ta billy
ps,, 30d

Edited by billy5 on Thursday 9th August 01:57

fixedwheelnut

744 posts

261 months

Saturday 11th August 2007
quotequote all
First try disconnecting the heater fan [hedgehog] resistor pack, if that does not drop the drain try disconnecting the main electric cooling fan in front of the radiator.

If they don't stop it then you have to isolate main circuits individually until you can narrow down which circuit on the car is playing up.

Did the RAC let the car go to sleep, up to twenty minutes before reading the drain? many don't and so get a false reading

Max current draw for an E39 should be 40 mili amps = 0.040 amps

To check if the car bus system has gone to sleep see if the auto gear indicator light has gone out or the glovebox light.

eliot

11,995 posts

283 months

Saturday 11th August 2007
quotequote all
fixedwheelnut said:

Max current draw for an E39 should be 40 mili amps = 0.040 amps

To check if the car bus system has gone to sleep see if the auto gear indicator light has gone out or the glovebox light.
How do you measure the current drain without disconnecting the battery to put a DVM in series (or have i answered my own question!)
Couple of weeks ago mine drained to nothing, I checked that the car was going to sleep as described above. Recharged the battery and its been fine since. But would like to understand why it just decided to drain the battery for no apparent reason.

fixedwheelnut

744 posts

261 months

Saturday 11th August 2007
quotequote all
Connect the digital multimeter to the battery earth terminal and the bodywork set up in DC Amps [usually the 10 amp range] once the car bus system has gone to sleep the earth connection to the bodywork can be disconected so then all current drain is going through the multimeter and can be measured. smile

rassi

2,517 posts

280 months

Saturday 11th August 2007
quotequote all
A similar problem and possible fix here: http://www.m5board.com/vbulletin/showthread.php?t=...

My guess would also be the final stage resistor or a faulty alarm system that will not allow the car to go into standby mode. http://www.540i6.com/finalstagereplacement.html

M5Dave

829 posts

238 months

Sunday 12th August 2007
quotequote all
Does the car have Sat Nav with Traffic Master. I had a similar problem with mine a couple of months ago, and it turned out to be the Traffic Master module that was causing the drain, I've since found out that this is a fairly common problem in the E39. Auto electrician removed the Traffic Master in less than an hour, and it's been fine ever since.

flossyjidge

15 posts

231 months

Monday 13th August 2007
quotequote all
Hi
I am Jayne - daughter of Billy5 who posted the problem for me!
Yes the car has sat nav - whats hedgehog?
Any one think I should just take it to BMW and pay the fee to sort it or will it cost me a fortune? I had an auto spark look at it & they said they could find no fault - that everything was working fine! Cost me £25 for nothing! He said the battery was not draining abnormally when he tested it!

A few things to add- the car (530d) seems to be very sensitive to 'hot sunny days'! when it is really hot the hazard lights flash for long periods of time - as if the alarm was going off,,,but no alarm sound - do you think it could be the alarm sensor inside the car? Also this seems to happen around the times when car is playing up and the battery has drained - for no apparent reason - when the car is locked and no key in the ignition. Its driving me crazy - I was out shopping the other day and after 4 hrs shop got back to the car & the hazard lights going off - thanks god no battery drain this time. Also sometimes when I lock the car I press it twice and this I think turns off the sensor the hazards still flash a times, Would it effect anythig else if I had the sensor in the ceiling of the car disconnected - In the meantime I have invested in a silly silver screen cover to reduce the heat inside the car - it's black leather and gets reallly warm so hope this might do the trick for now- waiting for the sun though! any more help would be greatly appreciated. Never had any problems like this with my old Audi A6! Cheers

flossyjidge

15 posts

231 months

Monday 13th August 2007
quotequote all
Hi Rassi

I checked out the site you put the thread on about - It is great - the exact same problem as I have! Strange it must be a common fault - I think I best get the BMW guys to look at it - I'll print off the replies from the 'unofficail bmw m5' page. No mention of the hazards flashing about though! Thanks - I have subscribed to that site too - looks good
cheers Jayne