another battery problem thread

[Moh153]

hi

My car wouldnt start this morning so used a booster to start it from the front

Then was fine all day till i left it for a few hours and its dead again

I had noticed that the "P" parking led by the gearshift was on but ive never seen this go off before

I read on here that it should go off after 16 minutes but nope

Any advice??

Thanks in advance

[X5Sport]

If the light is staying on that indicates something is keeping the car 'awake' as it should indeed go off after 16 mins or so.

First things to check are that all the doors and windows are fully closed, plus bootlids, sunroof and bonnet - look for whether the interior lights are going out when you lock the car (they should dim out immediately).

Have you got any optional non-oem hardware fitted (Hualingen, Intravee, iPod devices, extra Satnav or camera spotter etc.)

Richard

[Sanj]

If pre-facelift also chk the FSR/Hedgehog.

[Moh153]

The interior lights do dim out and go off when locked put the light by the gearshift doesn't go off after 16 mins

Also I don't have any optional gadgets in the car

Will check the hedgehog though might pull the fuse out for the blower and see if it drains the battery or not

Cheers for the advice so far guys

[Moh153]

Guys I've also noticed that the factory head unit goes off when I turn the car off but the sound stays on so I have to manually switch of the unit

[X5Sport]

That's sounding faulty then.  Mine always went off once the key was turned off.  It could be turned back on again though.....for either 30 or 60 mins if I remember - and then it shut down.

Not sure whether it's the radio unit itself, or some other area that controls the 'ignition off so shut down command', or if it can be programmed out with a scanner.

Depending upon car model you probably have either a BM24 or BM54 (Sanj will confirm) fitted and it might need repairing.  Not overly expensive, and way cheaper than a new one!!

Sounds like a error code read might be a good idea if nothing else comes to our other gurus on here.  That might show which control isn't shutting down and keeping the car awake.

R

[Moh153]

I'm sure I have the bm54 and it's definately the sound as when I switch the unit of manually and lock the vehicle there is still noise in the speakers of I put my ear to it

Also if I take the fuse out for the radio sat Nav number 7 it still stays on but the fuse isn't there

I have the hifi version with dsp

[Horizon]

Maybe its the amp net shutting down, if it was the radio you think music would be heard. If the amp is in the rear cubbyhole in the boot, you maybe able to pull the plug off and see if it cures the problem.

[X5Sport]

Also check fuses 72 & 73 - might both be in the rear fuse box?  I seem to remember fuse 41 being involved too, but that may be for resetting just the nav comp unit.  I can't find a diagram with the DSP fuse number on it - assuming it has it's own, though there is mention of the BM54 having it's own attached 10A fuse (red) physically on the unit.  Might be worth a tug in case it resets things.

Another area to check is whether there is any sign of water in the boot electronics bay down by the battery.  I know it means a bit of work to get at it, but if there's a leak it might be affecting the unit.  Water ingress is not unknown in these beasts.

You can of course always try the 'disconnect the battery for 20 mins reset'.  It is the simplest if not easiest process...

[Moh153]

right just took out the fuse number 72 in the boot and have disabled the radio sat nav and finally no noise in the speakers now once the car is locked so it has to be sound related

could be the audio relay, amplifier or the bm54 which is faulty