a friend of mine has an 85 rx7 and he was attempting to put a radio in it today and after he tried and failed he went to put the batterie back in and he put in backwards. while doing so he said that a relay box or something right next to the batterie mounted on the drivers side strut wall. im not around an rx7 to look at it now and he has told me all this over the phone. so im trying to help him out. from what he has described he says it has 3-4 wires that loop from itself back into itself. and he said when the had the cables connected to the batteries backwards that one of the cables heated up and turned red and then deteriorated. he said there was a cover over the wire but it just fell apart after it heated up and inside of it is a copper wire that broke from the heat i imagine. does he just need to get another wire(?) and it will be fixed or what should i tell him.

 

Sounds like he burnt up the main fusible link. Just need to find a new one, or do the 2nd gen fuse block conversion.

 

Yep, fusible links.....