GEN 1 Engine and power cutoff

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Couple more notes: I found Burnt and am replacing fuse 72 Under hood(auxillary power point rear). Not sure this will be the culprit but it needs to be done Anyway. I’m also going to check more closely and specifically for rodent wire chewing. Could it possibly be the ignition switch being faulty? I got it started it the last time it cut out by slowly turning key and manipulating it a little, and unlike other times where I need to wait for the power to come back on by itself and then turn key to start, this particular time turning the key turned the power on and it started the truck! Also, could it be an anti-theft function? I only have one key but not sure that matters, but it seems like computer is telling truck to shut off(either to disable due to theft, perceived accident, or a ground,power issue) but why would the hazard lights, locks,windows, headlights radio, be disabled and yet other minor electricals like seats still work? Shouldn’t the hazards work no matter what?
 

B E N

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Check the harness that is between the cylinder head and the firewall on the passenger side near the PCM. I think my fuse 72 blew when that harness wore through. Trace the wires from the starter back to the main harness, look for abrasion or removal of the sheathing. Check for Scotch Lock connectors, if you find any scotch locks, remove them, cut the wire, solder in a fresh section. The scotch locks will occasionally wear through the parent wire and should never be used on a PCM harness.

Could be antitheft, could be the lock cylinder. Next time it fails try the jiggle thing and you will know its the lock cylinder. Maybe @FordTechOne can shed some light on the power up order for the antitheft detector.
 
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FordTechOne

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Couple more notes: I found Burnt and am replacing fuse 72 Under hood(auxillary power point rear). Not sure this will be the culprit but it needs to be done Anyway. I’m also going to check more closely and specifically for rodent wire chewing. Could it possibly be the ignition switch being faulty? I got it started it the last time it cut out by slowly turning key and manipulating it a little, and unlike other times where I need to wait for the power to come back on by itself and then turn key to start, this particular time turning the key turned the power on and it started the truck! Also, could it be an anti-theft function? I only have one key but not sure that matters, but it seems like computer is telling truck to shut off(either to disable due to theft, perceived accident, or a ground,power issue) but why would the hazard lights, locks,windows, headlights radio, be disabled and yet other minor electricals like seats still work? Shouldn’t the hazards work no matter what?
Yes, the hazard lamps should work regardless of ignition position. The anti-theft system (PATS) will not disable an already running vehicle; it will only prevent the vehicle from starting initially if it cannot read the key. When that occurs, the theft light in the instrument cluster will blink rapidly.

It sounds like you are losing power to the majority of the vehicle, have you closely inspected your battery cables and terminals for loose connections or corrosion?
 

Skubik

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Do the fuse relocation, it's inexpensive and fairly easy. I bet that fixes the problem. It's not really the fuse that's the problem but the location of the fuse, it starts getting too hot not making a good connection and can even melt in place. While doing it keep a sharp eye for anything else that might look strange: loose or damaged wiring etc..
Also do all the other maintenance suggestions mentioned here: clean maf airflow sensor, filter etc..

More than a couple times I've set out to fix one thing and ended up finding a couple other items needing attention.

I hope you get this resolved soon, it's no fun driving in fear like that, been there with different cars.
 
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