my truck quit running the other day, i figured fuel pump issues because it would turn over, just not fire.

anyway... with the ignition in the on position, i could not hear the fuel pump run, so i did some schematic checking and went back to the fuel pump relay, but i shorted the teminals in the location to get the voltage to the fuel pump, it ran, and i could start the truck.

replaced the fuel pump relay and the eec relay, it started fine for the afternoon, then stopped again. i shorted the terminals again... but i need to know what the real problem is???

 

I believe either the PCM (powertrain control module) or ECM (engine) applies power to trigger the relay. You will need to get a wiring diagram to know for sure.

You could do a couple of simple checks at the relay, to figure out if power is applied to trigger the relay, or if ground is applied. If power is applied, you could just hotwire it to any hot in run ignition wire, theres probably 2 under the steering colum. But that is the all out "kentucky wind guauge" way of doing it. Do some checks and figure out if you arent getting power or arent getting ground to trigger the relay.

 

will do tomorrow afternoon... for now i will just hot wire it. thanks!