i have a 1997 ford f150 i replaced the GEM and fuse box i have bought 1 new gem an 3 used ones none worked. at first the truck would not crank the windows quit and the wipers quit when i replaced the gem an fuse box all this started working but now the plugs have no spark and no fuel pressure to fuel system i have fire to the coil packs but the plugs do not fire any ideas pleas i am now lost

 

It's hard to tell what you got into.
First, there are fuses involved with the PCM.
If one for the PCM is open the motor can still crank but nothing else will happen.
The coils have their own feed but unless the PCM addresses them by grounding the correct coil in the fire order, the motor won't run.
If the PCM has no power, likewise it cannot offer a ground to the fuel pump relay circuit
My guess is you lost power to the PCM for some reason.
Also if the PATS is out of power the motor won't start.
Not much help but to give some info to run with.
Good luck.

 

I don't know what GEM looks like But assuming a large wire bundle is connected to GEM, is it possible that one of the pins got bent? What if you put the old one back?

97 doesn't have PATS.

 

not sure what the pcm is, is that the gem? if not i will check it. am totaly lost will try anything. to recap what was rong and what i have done.

problems in order...
wipers quit
power windows quit
interior lamps flashed
head lights quit
truck quit starting
truck would not turn over with key but would if you crossed solenoid

repairs maid
put on two used gems then bought a new gem
(no help)
replaced fuse box
(all started working but no spark or fuel pressure)
have power to coil packs from wiring harness
have checked all fuses and mega fuses

 

PCM is power control module, or often called the computer. GEM general electrical module handles the less important things.

Does the fuel pump run? Do you hear it running when you turn the key on? Let me study my wiring diagram. If I find anything, I will post.

 

no i do not hear the fule pump start