Battery Problems

[wayne6511]

Hi,

I need some help or i will be forced to seel my beloved e30... as the wife will not put up with this anymore:)

I have a Hreg E30 325se and my problem is quite a simple one... my battery does not hold a charge and i am on my 2nd battery. The questions i have will help me in work out whats going on.

1. When i bought the car the battery was connected, Black Cable to Positive Red to Negative - the car has worked fine but does not hold a charge. Is this possible? i know that red is normally positive and black negative.

2. If i was to swap these round to what i think is right what are the implications of this ? blown fuses etc.

3. The reason i am worried about this is that a mechanic who changed the battery for me Wired it black positive and red negative again, surely this is something a mechanic would not get wrong ? am i missing something here ??

Any help or advice would be greatly appreciated.

Thanks
W

[Templ8e30]

The thick black cable is the positive and the brown is negative on E30's so it's fitted correctly.

Sounds like you have a power drain, could be a shagged alternator or some circuit like the heated rear screen etc.

If you have a multimeter check the voltage across the battery with the engine running, it should be about 14volts DC. If not you have an alternator or voltage regulator problem.

Cheers,

Iain T

[topspark]

A quick check is to disconnect the negative cable from battery (black one) and put a multimeter set to amps between the batterty lead and the battery post . Take the reading with eveything switched off. I you are measuring a current you have a fault. Then start pulling fuses until the current dissappers. I had the same problem and it was a dicky electric aerial.
Hi Iain,

lee

[wayne6511]

Thanks guys - i will give it a try at the weekend.