2002 ford super duty 7.3. where is glow plug control module located. can anybody help?

 

Just above the passenger side valve cover next to the AIH relay.






It's the aluminum colored rectangle box with 2 square plugs attached to it. Note: Only CA emissions trucks have a GPCM. The rest of them have a GPR.

 

since mine doesn't have a module (federal emissions) are the left bank and right bank glow plugs are controlled by the pcm? Also i replaced the the gpr twice and the big terminal going to the glow plugs doesn't have power when the ignition is on.

 

On a 2002, you have two relays next to each other. Make sure you're testing the right one. The PCM sends a ground signal to the glow plug relay to activate the relay and send power to the glow plugs.

Test the small posts on the GPR to see if you're getting a ground signal to one of them when the ignition is first turned on to see if it's a signal issue or a bad relay. (If you unplug the engine oil temp sensor first it will cause the GPR signal to be sent for two minutes giving you more time to test)

 

well both small wires on the gpr are showing 12 volts with ignition on

 

Engine cold? Glow plugs won't be activated if the engine temp or outside temp is warm enough.

 

won't star in cold weather, white smoke is showing when trying to start. took it to a mechnic his dyno showed bad pcm, gpr and left bank glow plugs not firing.

 

Lay a screwdriver across the two large posts for 30 seconds when it's cold out to power up the glow plugs.

Next, a dyno, or even a scanner is not going to tell you the passenger side bank of glow plugs is not working. There's nothing in the wiring or PCM to read that data.

 

k ty would you buy a pcm for a start?

 

Ummm... I suppose a loose UVCH would show one bank of glow plugs out, but I'd think you'd have other problems if that were the case.

Mark

 

well the pcm wire harness is kinda wonky on the firewall at the pcm