Battery Draining

Hi All

I was looking for some help…the battery on my 1992 Cabby keeps draining flat and I have no ideas where to start looking for the solution!

The car has an alarm, immobiliser, radio and thought it could be these. I have made sure no switches have been left on. The battery is fine.

Please could you give me some pointers as to where I should look myself before I have to take it to a garage (trying to save money after xmas!)

Thanks in advance

Andy

Firstly, measure the voltage of the battery when ignition is not on (and not been on for around half an hour), with the bonnet open (obviously) but doors etc closed.

then you could really do with rigging it up so you can measure current draw, and then turn the alarm on, etc.

Had same trouble with mine a few weeks back so i got a new battery which soon drained. It turned out to be the regulator on the alternator, the auto electrician only charged me ?20 and he fitted it too  8)

staffords said

Had same trouble with mine a few weeks back so i got a new battery which soon drained. It turned out to be the regulator on the alternator, the auto electrician only charged me ?20 and he fitted it too  8)

Hence, measure the voltages - on 'charge' a good alternator will give approx 14.3 volts. A lousy one (worn reg) less.

It's usually the regulator or a poor earth. If the battery is fine replace it and you'll have no more problems :0)

But to be sure and for the sake of not giving lazy answers.

connect just the alt to a fully charged battery and see if it drains or use a component checker on the regulator, or scope on the output from the alt. (if you have one)

*edit* to add something *usually one or more of the diodes in the regulator goes short(rarely open,unless its got a hole in it) so your can actually test for that with a normal resistance check if you know what your doing.

Hi guys…thanks for your help….going to get it sorted this weekend even if it kills me!
Andy