Fried alternator

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Twin Pinzies
Posts: 545
Joined: Mon Jan 03, 2005 1:33 pm
Location: San Juan Mountains, CO

Fried alternator

Post by Twin Pinzies » Fri Jun 23, 2017 8:01 pm

I made a mistake today...

My truck wouldn't start and I found that it wasn't getting any spark. Looking around the engine compartment, I noticed that the molex connector coming from the alternator wiring harness had shorted out and melted a couple of the wires in the connector.
I figured that until new wiring harnesses could be ordered, I'd just connect the wires together, bypassing the molex connector altogether by hard wiring it.

Well that didn't work out well at all... ... As soon as I connected the battery switch, the alternator pretty much caught fire. It happened instantly and I immediately turned the switch back off but it continued to smolder and put off heat. For about five minutes I emptied two vehicle fire extinguishers trying to keep it from going up in flames!

I know that I need a new alternator and wiring harness. I want to also replace the wiring harness that connects to the other side of the molex connector. What is it called or is there a part number?

Is there anything else I'm missing? Anyone ever had this happen? How did you fix it?

Thanks guys.

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United States of America
Posts: 1408
Joined: Sun Dec 10, 2006 7:38 pm
Location: Southwest Wisconsin

Re: Fried alternator

Post by pcolette » Fri Jun 23, 2017 8:56 pm

The wiring harness that goes from the molex to the alternator is here: ... 121090090/

The other part of it with the other half of the molex connector is part of the main wiring harness: ... 122852510/

I've replaced the first one to the alternator but only because it had become to corroded to clean up.
Paul C.
'73 Swiss 710M
'89 Puch 230GE
2002 MB G500 (For Sale)

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