Potentially major electrical problems ???
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Racer
Joined: May 2003
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From: Picton Ont.
Potentially major electrical problems ???
84' 928S 5 speed was in storage for 5 months and battery needed boosting. A "friend" was "helping" and reversed the polarity on the cables, I was not aware for a minute or two until I smelled overheated wiring. I have not attempted to start the engine since this fiasco. Before I have the car hauled 70 miles for service can you speculate which components may have been damaged and will require replacement / repair? Thanks.
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From: Ball Ground, GA
First, pull the battery cables and clean the connections carefully.
Use a standard charger to charge the battery fully - say, ten amp charger for a minimum of eight hours.
Reconnect the battery cables.
Try to start it - you may be lucky. You can always tow it later if necessary.
Remember that there may be numerous reasons that it won't start that are totally unrelated to the battery fiasco.
Let us know what happens.
Use a standard charger to charge the battery fully - say, ten amp charger for a minimum of eight hours.
Reconnect the battery cables.
Try to start it - you may be lucky. You can always tow it later if necessary.
Remember that there may be numerous reasons that it won't start that are totally unrelated to the battery fiasco.
Let us know what happens.
Thread Starter
Racer
Joined: May 2003
Posts: 457
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From: Picton Ont.
Thanks for the reply Wally. Let me clarify in case my note was misleading - I haven't even tried to start it sinced the charge cables were reversed. It wasn't a matter of trying to start it ---just don't want to do anymore damage to a "like new" 928.
If my note was not confusing then I will install a new battery and crank it over. Here's hoping I haven't fried any important components.
If my note was not confusing then I will install a new battery and crank it over. Here's hoping I haven't fried any important components.
Instructor
Joined: May 2001
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From: Saudi Arabia
Deb,
I doubt if trying to start it can do anything bad to the electrical systems.
If you are lucky then the shark will have escaped unharmed.
I was not so lucky. Just after I got my 85 I took it out for a highway cruise early one weekend morning. The battery shorted against the cover (which I then found out had no rubber or anything on the underside) Car was dead in the water. Had to tow it back. Cost me about $300 in electrical work on the harness mostly, a new ignition switch, some relays and one or two other bits I don't recall right now.
I hope you have better luck!
I doubt if trying to start it can do anything bad to the electrical systems.
If you are lucky then the shark will have escaped unharmed.
I was not so lucky. Just after I got my 85 I took it out for a highway cruise early one weekend morning. The battery shorted against the cover (which I then found out had no rubber or anything on the underside) Car was dead in the water. Had to tow it back. Cost me about $300 in electrical work on the harness mostly, a new ignition switch, some relays and one or two other bits I don't recall right now.
I hope you have better luck!
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From: Glen Mills, PA
Deb,
Reversed jumper cables are probably the #1 reason for a fried alternator. It will destroy the diodes in the alternator. If it starts and charges OK, it will seem that the alternator is OK, but it may have shorted diodes that allow it to charge OK but will drain the battery when not running. Have a competent electrical shop check the alternator.
Reversed jumper cables are probably the #1 reason for a fried alternator. It will destroy the diodes in the alternator. If it starts and charges OK, it will seem that the alternator is OK, but it may have shorted diodes that allow it to charge OK but will drain the battery when not running. Have a competent electrical shop check the alternator.