Battery Light On Again - ugh! - Need Advice

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Crit
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Joined: Wed Mar 04, 2009 12:39 am
Location: Solvang, CA

Battery Light On Again - ugh! - Need Advice

Post by Crit »



A number of months ago the battery light came on weakly. I put new brushes on and it seemed to help some but the light still was on and the car was not starting easily. So I went to the local garage, they said alternator output was fine but the battery was only at 60% (this was after it was on the charger all night). So I got a new battery and everything was fine for about 2 weeks.

Then the battery light came on weakly and would glow brighter for awhile and then get faint again. So for a number of months I would put the car on the charger at night just to get by. Then a number of weeks ago the battery light intensity increased to full so I took the car to my real mechanic. He said the alternator was shot so I bought one and installed it myself a few days ago.

Everything is working great but the battery light is again on very faintly and when I turn on the blinkers or hit the brakes, etc. it will temporarily glow a little brighter. So far if I did not look for the light on I would not think anything is amiss as the car starts and runs great.

Is anything actually wrong here and if so what next to I check? Also the new altenator came with a voltage regulator but there was a small wire/plug with screw right next to it that I had to transfer from the old unit as there was not one on the new unit. What is that piece? Also the only thing that I did wrong on the alternator install was that I disconnected the battery positive lead instead of the negative.

Crit Taylor
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Lenny D.
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Post by Lenny D. »

I might suggest you have (or better, make) a good ground strap from the alt. to the engine (and ultimately the battery ground) with something like #10g. wire and solder the connectors on each end. It sounds like the battery is not getting charged.
You must have happy electrons!
HTH

'80 528i
Milan
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Post by Milan »

Lenny D my wire guru. listen to this man !!!
Karl in KS
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Post by Karl in KS »

I did that on my car and it helped -- heavy wire from alternator case to engine block to battery ground.
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