alternator ,battery light help
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From: stoke on trent
my car is not charging when running also the battery light on the dash isnt coming on,ive checked the bulb and its fine
ive also ran a wire from the alternator to the bulb and it still doesnt come on
fucked allternator? i thought the battery light would come on if the alternator was naffed not vice versa
any ideas before i buy another alternator?
ive also ran a wire from the alternator to the bulb and it still doesnt come on
fucked allternator? i thought the battery light would come on if the alternator was naffed not vice versa
any ideas before i buy another alternator?
Theres a thin blue wire going to the alternator, should be a bullet connector on it close to the alternator, turn the ignition on and short the side coming from the main loom to earth, the bulb should illuminate then, if not theres a wiring fault.
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From: stoke on trent
cheers mate never thought of that,will give it a try tommorow
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From: stoke on trent
i took a wire from were the blue wire plugs on the alternator direct to the bulb turned the ingnition on and still no battery light and no charge going into my battery
you need to take the dash out find out which wire gives power to the light, (not the blue one) and then test that that wire gives ing live.
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From: stoke on trent
i had the starter and alternator off a few weeks ago all was fine before that. ive checked the wires a dozen times and everything seems fine
cant get my head round it at the min lol but im shit electrics

cant get my head round it at the min lol but im shit electrics
are the other warning lights and gauges working then??
Seems a bit coincidental you had them both off and now you have a fault though.
Are you 100% the buld isnt getting a feed from the instruments, like checking with a multimeter or test lamp?
Seems a bit coincidental you had them both off and now you have a fault though.
Are you 100% the buld isnt getting a feed from the instruments, like checking with a multimeter or test lamp?
Last edited by SafeChav; Jul 26, 2008 at 09:09 PM.
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From: stoke on trent
it is coincidental i know ,thats whats doing my nut in lol
wouldnt the other warning lights not work if it wasnt getting a feed from the instruments? whats best way to check with my multimeter?
You need to try shorting that blue wire to earth (ignition on but NOT with the engine running)
I have a nasty feeling you may well have popped the diode pack in the alternator.......
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From: stoke on trent
Well........they all share the same ignition feed, so if they are working i cant see it being a lack of power.
You need to try shorting that blue wire to earth (ignition on but NOT with the engine running)
I have a nasty feeling you may well have popped the diode pack in the alternator.......
You need to try shorting that blue wire to earth (ignition on but NOT with the engine running)
I have a nasty feeling you may well have popped the diode pack in the alternator.......
cheers for the help
I had this problem, after my mate checked a few things we found the wire to be broken somewhere, instead of searching for it we just put a new wire in, taped to the loom and was fixed in about 15min!
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From: stoke on trent
update, starting to piss me off now
earthed the blue wire and turned the ignition on and my battery light comes on.
so i take the alternator to a place that specialises in that shit and they said theyll test it and ring me back.
couple hours later they ring and say theyve managed to fix it theyve put a new regulator on for £30 and its working fine.
so i go get it wire it up to the car and no fucking battery still
wtf!!
just took it back to them to test again because i cant think wtf else i can try
earthed the blue wire and turned the ignition on and my battery light comes on.
so i take the alternator to a place that specialises in that shit and they said theyll test it and ring me back.
couple hours later they ring and say theyve managed to fix it theyve put a new regulator on for £30 and its working fine.
so i go get it wire it up to the car and no fucking battery still

wtf!!
just took it back to them to test again because i cant think wtf else i can try
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From: stoke on trent

i had the bracket and other bits powered coated a bit ago and never grinded the powdercoat off the alternator bracket before i put it back on
what a dumb fuck
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From: stoke on trent
I tell you what ill swap my fault with yours and we will be both happy lol
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From: stoke on trent
well thats that problem sorted. battery light comes on now but the fuckers staying on and still my batterys not being charged 
im hoping its down to the fact ive only got one bottom bolt on because the other cross threaded, belt feels tight though still
happy days

im hoping its down to the fact ive only got one bottom bolt on because the other cross threaded, belt feels tight though still
happy days
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From: stoke on trent

it was only on one bolt to test to see if it worked ,the other one cross threaded but ive got a replacement now
i think its a bad earth still giving me problems ive taken the bracket off again and grinded more of the powdercoat off .will find out tommorow
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From: stoke on trent
it stayed on and went off ,i checked the battery with my multimeter and it wasnt charging so i turned the car off then tried the ingnition again and no battery light again
It's surprising how common the bad alternator earth problems are. It's easy to measure with a multimeter. With engine running measure the voltage between the alternator casing and battery negative. It should obviously be close to zero. Over 0.5V and you're having serious problems.
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