alternator dead or not?

Honest John Back Room » Technical matters
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Sat 10 May 2003 17:53
alternator dead or not? - rcflyers
As I pulled away from work last night all my car (1994 Astra 1.7 TD) electrics went dead and loads of smoke came from under the bonnet.
A wire from battery to alternator had chafed through and shorted. I have replaced the burnt out wiring this morning and cannot find anything else damaged, but the alternator now won't charge. (rev counter wont work and the charge light stays on)
Could the alternator have been damaged by shorting the 12v output wire to earth while it was running?
Anything else to look out for?
Thanks for any help
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Sat 10 May 2003 21:32
alternator dead or not? - frostbite
Since no-one else has rushed in here, it may help if I mention a similar problem I had several years ago.

I discovered that the diodes had fried and replacing them brought it all back to life.
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Sat 10 May 2003 22:31
alternator dead or not? - Robin the Technician
You have indeed fried the diodes inside the alternator. Replacing them is not so easy so its probably best to replace it with an exchange unit. Even this is'nt so easy as according to the Unipart (where I work) catalogue there are five different types ranging from Bosch to Delco Remy. I would suggest you remove it and take it with you when you go to get a replacement.

Theses are the views of robin the Technician with 35 years in the trade. I fix, therefore i am....
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Sun 11 May 2003 15:31
alternator dead or not? - Peter D
Yes dead I'm afraid. The alternator is used to drive the rev counter in the diesel model thus that is not working as either. Sorry Regards


Peter
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