Hey yall, I have a 1987 F-150 Short Wheel Base 2WD, 300 6Cyl. with a electrical problem. When the truck is running without any accessories (Lights, Wipers, A/C etc) It runs great. As I turn on each accessory, I can watch my amp guage creep down. When I run the A/C it will eventually kill my battery.

I have changed the Alternator and battery cables but this did not seem to help. I am thinking that I may possibly have a ground loose or broken somewhere. Does anyone know where I can locate a electrical drawing that may show me where all the grounds could be located on this truck? I don't want to leave any of them out when I go to hunt them down. Any help would be greatly appreciated!

 

Haynes manuals have wiring diagrams, but they don't tell locations of the grounds. You're probably going to have to hunt them out. There is one engine to firewall, possibly others engine to frame, many other straps throughout from frame to body, main engine harness I think bolted near thermostat, main harness under dashboard, and various others everywhere. I have just added extras here and there sometimes and fixed problems that way, you can't have too many grounds.

 

Ford has tech manuals for just this thing. EVTM is the name. Try helm.com I think its a $9.00 charge for 3 days useage. Naturally have the make, model and year on hand. In this manual, they call out exactly where the splices, connectors and grounds are.

 

Thanks guys, I will look into your suggestions and let you know what I find out.