Reversed battery cables

[75850]

Inadvertently reversed cables on 75 Merc 850. Only visible damage was burned insulation on red lead to switch box. When cables corrected, get hot spark at contact when reconnecting cables with key on. Sounds to me like I fried the switch box, have ordered replacement. Any other likely damage?

 

[Laddies]

Re: Reversed battery cables

The chances are you fried the rectifier and switch box

 

[tashasdaddy]

Re: Reversed battery cables

yeap.

 

[75850]

Re: Reversed battery cables

If the rectifier is gone, do I risk damaging the new switchbox? How do I check the rectifier?

 

[Laddies]

Re: Reversed battery cables

There is a 99.9% chance the rectifier is fried, use a OHM meter and ck continuity the diodes will only allow a reading 1 way, if the diodes are open both ways it,s bad or if either is shorted to ground it's bad

 

[75850]

Re: Reversed battery cables

Thank you for the help. Rectifier is gone, will replace.