#7 GP circuit Failure

[63wagon]

I have a 01 California Powerstroke. I have a service engine light with code p0677 which when I researched on here found to be a number 7 glow plug circuit failure. I want to clear the water a bit before I throw parts at it. Could it be as simple as the number 7 glow plug has failed or a problem in the California exclusive glow plug controller module?

Also, there appears to be a glow plug relay next to the controller module. It does not power the glow plugs but rather some sort of intake air heater. I used a multimeter and tested it similarly to testing a gp relay but had no volts on the intake air heater side. Could this be controlled by the module as well?

[63wagon]

No one has any ideas?

[jesilvas]

That is the air intake heater. Pcm controlled. I wouldn't worry about it.
The bad gp could be a bad gp or a bad uvch. You'll need to ohm the harness and plug out.
There is a sticky thread on how to do so

I made my Samsung SGH-I997 send this.