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Discussion Starter · #1 · (Edited)
Help!
I had Charing issues some months ago and took to shop. Battery wasn't getting a charge and volts would fall below 11v while driving....Replaced Bosch Alternator and Battery. Everything fine for 4 months.

Red Battery Lite came on and Battery Test 09 saying 11.5v and drops down to 10v while driving...same issue!
Thoughts?? :crying

Thanks!
David
 

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Try replacing your negative battery cable... I had to go through 3 of them until it all finally stopped being a problem.

Also I had to go through 3 batteries till I found one that would hold a charge, could be a bad cell IN the battery.

Good luck.
 

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Discussion Starter · #3 ·
Batt is brand new and we did test when purchased so i fairly confident that is not this issue...
interesting thought about Neg Batt Cable... what symptoms you have that led you believe you neg batt cable was the problem??
 

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Batt is brand new and we did test when purchased so i fairly confident that is not this issue...
interesting thought about Neg Batt Cable... what symptoms you have that led you believe you neg batt cable was the problem??
I wouldnt use the word symptoms that led me to my solution it was more luck and finances.

When I first started having a drain/charge holding issues, I would disconnect the negative cable when parked to stop the drain.

I finally got around to replacing my battery and lo and behold it still wouldnt hold a charge, back to the store I went, bad battery.

Replacement of the battery still no holding charge...

I bought a cable from Adam (Clemster) and still issues with charing battery, had it tested,

Rinse... repeat... until finally I (3 batteries and 3 cables later) ***knock on some SERIOUS wood*** have been running strong for 8-9 months now.

Adam if you read this, or, anyone who is a customer of Clemter's he provided me great customer service!! As did Adavanced Auto Parts.

In case you are wondering, all of the battery/stress tests tested the alternator so I was able to rule that out.

I think in the end I was a victim of timing and my own stubbornness. I think I had 2 bad batteries and my first cable went bad because i broke the fibers by taking it on and off so often. For some reason the 2nd cable may or may not have been as strong as stock from age/wear-tear etc.

I still would love to know exactly what went wrong but in the end (so far) I am running solid.

So to answer your question... I have no solid idea why or how I got to my diagnosis.
 
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Discussion Starter · #5 ·
no solid idea on my end either...
finally broke down when Test #9 read that the batt was at 9.8v and limped her to the shop. They did their tests and said the alternator was to blame.... i had replaced the alternator 4 months ago!! Brand new Bosch OEM alternator and it died in 4 months. thankfully under warranty but still have to pay for install. :(
Anyone else had new dud alternators? is that rare/common?
 

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It's probably the voltage regulator that went bad. It's an electronic component and I guess 4 months is within the early part of the bathtub curve, so to speak. Anyway, new alternator will have a new regulator so you should be good.
 
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