I have already searched a lot of the other forums for an answer and came up short. The truck is an 06 F-350 6.0 w/144,000 miles. I went to go to work the other day and my check engine light came on. Took it to Advance Auto and it came back with Glow Plug circuit #2 fault and it showed that the code had been thrown 3 times. I did the OHM test on the glow plugs and they all checked out at 0.7 ohms, which lead me to believe it was the GPCM. Since Advance forgot to clear the code, I unhooked the batteries for 30 sec to clear the code and restarted the truck. No check engine light this time. Drove the truck around for a bit as well as turning the ignition on and off multiple times. Still no light. Not that I'm complaining that the light isn't coming back on but I'm lost as to what was causing the code to begin with or could it be just queer-trons? Any help would be much appreciated. Thanks

 

Moved to the 6.0L Powerstroke Diesel forum.

 

Could also be corrosion on the plug. Best is to clean both
plugs and the bottom of the GPCM. Then apply some
dielectric grease to the plugs and see if that fixes the problem.

Sean

 

Thanks, appreciate it....I'm still a rookie when it comes to posting threads

 

I checked for corrosion when I had it all unplugged and it was clean as a whistle. I guess as long as I don't get another CEL I'm good but trying to figure out what gave me the code in the first place is a little bit of a curve ball. Usually on parts like that it either works or it doesn't. We'll see what happens over the next few days. Thanks for the info.

 

I would still put some dielectric grease on the plugs to keep
them in good shape.

Sean

 

I've had a few of these glow plug codes - mine have gone off for a while too, but they always come back on. In my case it has always been the glow plugs. They are pretty easy to swap and cheap. GPCM is over $100. I agree with the dielectric grease. At least once the glow plug tested OK but the light stayed off after a new one (the other time I did not bother with the testing, just swapped it out). If the light stays off, I would not worry about it. Maybe it was a bad connection that you fixed just doing the testing - disconnect, reconnect.

 

Yeah I'm hoping it's that easy. When I first got the light I went ahead and bought 8 new glow plugs and wiring harnesses for both sides and of course it fixed itself after I spent all that money on parts. I'm pretty sure that it has original glow plugs and wiring harness on it. You think I'm better of to just replace it all since I have all the parts? Knowing my luck the day I send all the parts back to get my money back the light will come on again

 

That leads me to beleive it is the GPCM as well

But the Circuit might be Open Only when cold so it may take a cold soak cycle or 2 to throw the DTC Again

So if you checked (OHM) them when Hot Might be good to check them Cold After 12 hours cold soak

Hot/Cold & Expaned/Contract does weird electrical stuff

Could be a wire Chafe to But if its really been triggered 3 times its coming back so Keep the Parts


And write down the exact DTC next time

 

When I originally tested the glow plugs the truck had been sitting for 3 days with out running. I inspected for possible wire chaffing when I was under the hood but couldn't really see anything that led me to believe that might be the problem. The code I was getting was P0672 - Glow Plug no. 2 circuit fault. I know this is probably in another thread somewhere but any way to test the GPCM? I absolutely hate trying to diagnose electrical problems

 

Were you thinking about this post?

https://www.ford-trucks.com/forums/1...ce-manual.html

Here is what I had to say,

Sean

 

Update: I've been driving the truck all week and it never has thrown the code again. So hopefully it fixed itself. Thanks everyone for all the advice/help.