Hi guys, Ive got an 03 Ford f150 Heritage truck V6, no power at fuel pump, checked all relays and fuses also, checked the inertia switch on ride side kicker panel was told needed voltage on both sides, no power there either, the old pump was bad, I bench tested it bad, , bought a new one, but cant get power to it, any ideas? Thanks.
Check the inertia switch for power key for only 2 seconds. Power will return cranking.
If not, back up to the relay and check for power at 2 terminals. The pcm grounds the relay.
If no power, possible ignition switch or fuse.
July, 23, 2012 AT 4:18 PM
Going to check right now, wasnt aware of the 2 sec window on inertia switch, I only found power at one terminal on relay, first time I checked.
July, 23, 2012 AT 4:28 PM
Just checked the inertia switch, within 2 sec window and crank, no power going to recheck all my fuses and relays, You mentioned power on two terminals at relay?
July, 23, 2012 AT 4:34 PM
It look s like there are 2 fuses for the relay
July, 23, 2012 AT 7:36 PM
I checked the 2 fuses and 1 relay all have power I understood im suppose to have power for two secs upon ignition ON at relay terminal 87open circ to 87close circ when grounding? NO power at inertia switch on two second ignition key on on test.
July, 23, 2012 AT 7:52 PM
If you can energise the relay, see if it powers the pump.
July, 23, 2012 AT 8:24 PM
About to check that, let me see if I can energize the relay, what about the inertia switch, and doesnt the ignition switch send power to pump also?
July, 23, 2012 AT 8:54 PM
Yep but you need power to the switch before it can send power anywhere
July, 23, 2012 AT 9:39 PM
I jumped off term 86 to 85 with pigtail, I did get 12 volt to pump plug, but unable to shut off voltage with key at pump plug, did have continuity to ground on black line, and constant 11.5 volts on yellow lead at pump plug, inertia switch jumped out also, .
July, 23, 2012 AT 11:22 PM
I wish you had a scan tool as you could energise the fuel pump relay from the scanner to verify control circuits before condemning the pcm