E34 battery drain problem HELP!!

[MIZTERIO]

Hello guys I need your help with my 1991 525i battery drain problem. Originally I bought a new Battery (Duralast) on september 2006. The battery was doing good all that time. On February 15 my car was completely dead, no interior light not even the car alarm was working NO ENERGY at all. The battery had a warranty I took to the store adn replaced for a new one. I installed my new fresh battery on february 16, 3 days later the car was dead AGAIN! no interior lights, no signs of life , not even the car alarm was working. the first battery last me for 5 months and the second battery for 3 days. what can be the problem?? what can be draining the battery??

thanks guys in advance!!!

[87' 325]

If you drive it alot it may be the alternator.

[xLibelle]

when you hook up the polls, does it spark a little?
you need to perform a leak test AND have an auto store check your alternator

[AdamF 88iS]

Check if any of the power seat switches are getting stuck.

If thats not it, pick up a multi meter that can measure load. Hook up the meter and pull fuses one at a time until the draw disappears... then you'll know where to look.

[MIZTERIO]

when you hook up the polls, does it spark a little?
you need to perform a leak test AND have an auto store check your alternator

yeah it sparks alittle.... I forgot to mention the store check the alternator.. he said something like 13.6 v.. he said it was goog. :roll:

[MIZTERIO]

Check if any of the power seat switches are getting stuck.

If thats not it, pick up a multi meter that can measure load. Hook up the meter and pull fuses one at a time until the draw disappears... then you'll know where to look.

i barely use the power seats.... I checked them anyway and they are not stuck.. am gonna buy a meter and do that test..

any more sugestions???

THANKS GUYS!!

[Nick]

Again, a blown voltage regulator on the alternator can cause this problem.

I had a problem like this on my old e32...it ran fine, then poof, no power.

It ended up being a bad alternator.

[AdamF 88iS]

Again, a blown voltage regulator on the alternator can cause this problem.

I had a problem like this on my old e32...it ran fine, then poof, no power.

It ended up being a bad alternator.

True, but he tested 13.6v, which is pretty text book. If it was charging at 14+ then yea, bad regulator.