Battery connected backwards on my Volvo Penta 5.7, now electrical issues!

HawaiianHooker

Seaman Apprentice
Joined
Aug 23, 2005
Messages
41
My friend was helping out, connected a ground to a hot lead and when we turned the battery switch on, it caught fire.

We put it out pretty quickly but now I have electrical issues.

The Fuel Injectors won't come on, thus the motor will not start.

Has this happened to you, do you know what the likely cause could be?

The obvious has been done, replaced switch, bad wires....

Thanks...

it's a 99 Vovlo Penta 5.7gsi-pwtr
 

gm280

Supreme Mariner
Joined
Jun 26, 2011
Messages
14,605
Oh wow, so sorry to hear that. You maybe looking for a lot of new electric parts now. Most anything that didn't have some internal power supply could be fried. And that also can mean a new computer for the engine. They just don't like reverse current for some strange reason. So I don't think your injectors are toast, but that will be reviled later on. You now have to remove or at least disconnect electrical things and test them to see if they are still working. Check your starter solenoid, the actual starter itself and move on from there. But anything that can't take a reverse current it probably toast. I don't think your switches will be bad. They really don't care which way current flows through them UNLESS they are the illuminated type (toggle LED type). Then you could need switches as well. Also any wires that look good should be okay as well. But test them to verify they are still good. And if you don't have a meter, use a 12 volt tester light on the wires...only after there are disconnect from everything else of course. :sorry:
 
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Dave-R

Chief Petty Officer
Joined
Mar 18, 2008
Messages
441
If you do get it running again, the diodes in the alternator are usually shot. Depending on the model you have, there are inline diodes that are in the wiring from the starter, and the alternator that feed the fuel pump relay. They also are shot when this happens, and are hard to find. I never take any ones word for the connections when using jumpers, you won't either. Good luck , Dave-R
 

Thalasso

Commander
Joined
Jan 18, 2011
Messages
2,879
If you do get it running again, the diodes in the alternator are usually shot. Depending on the model you have, there are inline diodes that are in the wiring from the starter, and the alternator that feed the fuel pump relay. They also are shot when this happens, and are hard to find. I never take any ones word for the connections when using jumpers, you won't either. Good luck , Dave-R

Delete.
 
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kkirt1

Cadet
Joined
Feb 3, 2009
Messages
11
I did the same thing to my boat. It required a new wiring harness. Insurance covered my idiot move! Good luck!
 
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