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Discussion Starter #1
My car hasnt been used much at all since September of last year, and for the past couple of weeks I've had to use a booster pack to aid starting the car, after which, a short drive and all seemed well, with her starting on her own easily, no "battery" light illuminated or anything like that.

However a day or two ago, I was starting her to take her to the garage to have some other work done and knew I'd probably have to use the booster battery again to start her, done same as before but noticed that instad of being able to do it from under the bonnet, using the + terminal and an earth, I had to go straight to the battery itself, I simply pu this down to getting a better connection at the battery, and ofcourse the car started. I removed my booster and started to get organised to leave, when I noticed my ABS light come on, followed by and EDC NOT ACTIVE, AIR BAG etc and then car died. Thought, strange, so went through same procedure agian with booster and every time I removed, the car would only run for a min or two before dying.

I thought I had better replace the battery which I did, new Bosch number and started the car on its own this morning, however, Voltage readings from the battery when disconnected and connected read about 12.5v and with the engine running, read 11.2v or there abouts :sad2:

I've always had the understanding that on reving the engine, I hsould be able to record 14v or so indicating charging.

Also the "battery" light on the dash is illuminating slightly.

An additional point, may be irrelevent, when I take a voltage reading from under the bonnet, + terminal and an earth, I'm reading about 12.2v compared to directly on the battery terminals at 12.5v Is this a concern in itself?

So what do you guys think, a knackered alternator:grrrr:
Or could I have simply blown a fuse somewhere with my booster starting battery:dunno:

Ofcourse, problem I have now is driving car to Dealer knowing that I'm on battery alone and also knowing their tendency to charge £££/$$$:crying:

Any quick opinions or magic fuses to check before I melt another credit card?

Thanks
 

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It's always worth a complete fuse check,
but it sounds like the regulator/rectifier in the alternator
has gone down.
Sadly it probably did get a spike during jump starting.


Regards,

Alan
 

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Ofcourse, problem I have now is driving car to Dealer knowing that I'm on battery alone and also knowing their tendency to charge £££/$$$:crying:

Any quick opinions or magic fuses to check before I melt another credit card?

Thanks
Probably just the regulator in your alternator.

You could try and do this yourself. You only have to remove airfilterbox / maf / rubber boot to plenum. It's a bit of a fiddle but the alternator will come out. (edit: on a 3.6, hope 3.8 has the same room)

Take it to a shop that overhauls alternators and have them test it and replace the regulator.

My shop does this for 50 Euros

Cheers
Ray
 

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Discussion Starter #4
I think if the dealer says its the alternator, I'll take it to an alternator place and have them check it over, as I know paying for the dealer to remove and refit and the alternator shop to replace and individual component or indeed overhaul would still come out at less than a dealer supply/fit price.

Will see what they say tomorrow, I had a look to see how accessable it would be to remove and refit but it does see like a tight squeeze, like almost everything else on these things.
 

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take the voltage regulator out of the back of the alternator, check if its in one piece, if it is you can then check how worn it is
 

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The Bosch alternator is the Rolls Royce of Alternators.
They hardly ever fail completely.
You will have to remove it from the car to test & inspect regulator / brushes.
I agree with the take off & test.
Both Geach & I have have rebuilt our own.
Mine put out over 140 amp on a alternator test rig.

Farrell
 

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Hello Plisken. Sound's exactly like the symptoms my car displayed when the alternator packed up. I had it completely overhauled for about £120. IIRC, there is a place in Bellshill that could repair it for you. Don't have their name to hand but I can get it when I'm at work.
 

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Discussion Starter #10
Shandon Electrics, many a starter and alternator have they done for me in the past, probably about a dozen or so for my Capri'slovelove

Need to go into the garage for a few other bits and bobs anyway so if they say alternator is dead then I'll most probably go down the Shandon route.

Cheers...cherrsagai
 

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Hey plisken,
I had the same symptoms as you a couple of months ago..low battery, ABS light coming on along with other warning lights. Took the alternator off and carried it to a local alternator shop...the brushes were worn out. They did what they call a minor rebuild, checked and lubed all bearings, turned the rotor where the brushes contact, checked out the regulator, and replaced the brushes with Bosch brushes, cleaned it up, reassembled and tested. Fixed the problem and runs like new....all for $52 US. ($4 parts & $48 labor). They recognized the quality and said it should be good for another 15 years or so. Can't beat that.
Good luck!
 

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Discussion Starter #13
Car in Stealers as we speak, however on starting the car this morning, Battery light and alo Handbrake light were on and remained on for about 5 minutes or so after which time they both went out at the same time and I thought I would check Voltage at battery now, 13.7v at idle, hmmm, seems like we are charging again.

Still not had any feedback from Stealer, except that they would need another hour for diagnosis (£81/hour)
They are also looking into my recurring EDC fault but I wont hold my breath on that one either.

Anyway back to point, the battery light being on, this I can understand as it would point towards the car not charging properly, but why both the battery light and the Handbrake light? Very strange.:lightbulb:
 

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I agree..it is strange...but I experienced basically the same issues with various warning lights coming on...in addition to the charging indicator. Dont remember which ones came on...maybe all of them...it was lighting up like a christmas tree on the dash..and since this occurred at night...headlights went dimmer and dimmer. Went totally dead and coasted in to the liquor store. haha
Let me know how it turns out....that is if you can trust what the stealer tells you they found.
 

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Would an alternator stiffen up under load ?

I keep shredding belts and the only thing I can think of is that the alternator is at fault ?

When cold it moves freely though..................
 
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