got a 91 4.9l 4speed manual. couple weeks ago truck died while driving. no heater, dash lights, door chime. after towing it home it worked? checked all the grounding from battery and it all seems good. today it did it agian. lights work. but all systems that should come on when key is turned do not work. i replaces the ignition switch, but that didn't help. any other ideas for me? thanks

 

Did you test the battery and alternator? It sounds like it grounding out somewhere and killing the engine. Be sure to look over everything and electrical connections, check battery cables aren't grounding on the frame or engine where they aren't supposed to.

 

i pulled and tested alternator last time and it was fine. i checked the negative for proper grounding, and it looks good. i havn't checked the positive for improper grounding. ill try it thaanks