Glow Plug Relay with Shunt - Wiring??

[Hawkeyes]

I planned to replace my Motorcraft GPR with the Stancor model, but my 2000 model 7.3 has the flat metal shunt separating right and left bank glow plug connections. I tried using the Stancor with the shunt, but threw an SES code, "low power to right and left bank glow plugs".

I then reinstalled the original GPR, but still get the same SES code.

I'd like to make sure I have it wired correctly - I have the 10ga yellow wire to the top (closest to firewall) shunt connection along with the green stripe 14ga wire (blue end).

I have the 10ga brown wire to the bottom (closest to the radiator) shunt connection, along with the white 14ga wire (blue end).

I have the 14ga purple stripe wire (blue end) to the large copper GPR/center shunt connection.

Red and orange 14ga wires are connected to the two small silver connectors on GPR; the orange and black power lead is connected to the other large copper GPR connector.

Is this correct? Does someone know or can look at their truck to see if I've got it right? I reset the SES, but keeps coming back. Glow plugs were all replaced last January, along with the GPR - all worked fine until I messed with it. Doh.

Thanks!!

[Jeremy]

Just a guess here but if your getting a code you might have a GPCM. Something may have messed up the GPCM. Califorina rigs came with them, and maybe the Ex's did too. Its a silver box(~2"x5" with two large connectors one of them is green, should be right aound the relay area.

[jgarden]

See if this helps. Did you reinstall the shunt? Did the shunt fit on the different GPR. Was the GPR you installed a different size than the OEM GPR? If so how did you reinstall the GPR? CA rigs do not have a GPCM and GPR, it is one or the other. I thought they went to the GPCM in 2000. I thought only the 99s and earlier CA rigs had the GPR with shunt.

[Hawkeyes]

Jeremy - no silver box on mine, must be late 99 or early 2000.

Jgarden - Yes, I reinstalled the shunt. It didn't fit on the Stancor same way it did on OEM relay, but I bent the 'legs' out so I could attach it. Yeah, the Stancor is much larger & different face than the other, but can be mounted on the same bracket. Because it kept throwing the code, I put the old relay back in, but now it too is throwing the same code. That's why I wanted to check the PCM wiring to the three-connection shunt. I'm pretty sure it makes a difference because the PCM checks resistance, then compares for each bank of glow plugs so main connection to PCM must be at center (middle) shunt connection.

Because each PCM wire has a blue end, it's not easy to see what the actual wire color coding is, at least not from your pictures. I have a white with green stripe, white with purple stripe, and what appears to be a solid white or off-white. My heavy wires, Brown and Yellow are connected like your photo shows. I have the green stripe connected to Brown and purple stripe connected to Yellow, with white connected to copper relay terminal. This creates an SES light/code for low power to right and left bank glow plugs. So it must be wrong configuration.

I need to know which striped wire goes to which connector - that should be enough to at least make sure I have it wired properly.

Thanks for your help!

Hawk

[jgarden]

HAWK,

I went out and looked at my truck.

The blue wire that turns into the white/green (after the fuse link) is connected to the center post.

The blue wire that turns into the white/purple (after the fuse link) is connected to the forward (closest to the radiator) post.

The blue wire connected to the rear most post I didnt look at that white wire as it was buried in the loom. That will be the leftover color. If you really need me to look at that one I will push up the loom and check it.

Hopefully this is helpful and will solve your problem.

Is the code clearing and then resetting after you start the truck? Make sure you code is actually clearing.

Also, make sure your GPR is not the problem. You talked about putting in the old GPR, are you sure that one is working?

FWIW, I got the low left and right bank SES codes when my GPR was bad.

[Hawkeyes]

Jack,

Thanks a million for your help. I wired it up like yours and 'voila' no more SES light. Right now I'm going to leave well enough alone, carry the Stancor as a spare.

Thanks again.

Hawkeye

[jgarden]

Hawk, was your original GPR bad to begin with or were you just doing an "upgrade"?

I am in So Cal, so my GPR doesnt get as much a workout as the others out there. My OEM GPR lasted a little over 10 years, so I just replaced it with another OEM one (purchased from International for $30). I thought about doing the Stancor, but with the shunt it looked like it would be difficult, and the OEM one fits like a glove in the location Ford put it. Anyhow, I just left well enough alone....and hope I get another 10 yrs out of it.

I see you are in Minnesota, so your GPR will work alot harder than mine. It seems some of the guys who are in "cold country" sometimes only get a yr out of the GPR, if that is the case I can totally understand the "upgrade."

Anyhow, glad I could help. I have received so much priceless help from this board in the last 10+ years, I am always thrilled when I can give back.

[Hawkeyes]

Jack,

I had a starting problem last winter, brought it to the local dealer (big mistake) who felt the best way to check the electrical circuit was to start replacing components. Starter, glow plugs, glow plug relay, alternator wire. Still didn't fix the problem (sometimes start, sometimes nothing - like a bad neutral safety switch). I did some online research, went to Autozone & bought a $12 replacement for the fender-mounted relay and solved it. So the GRP is less than a year old. I just felt the Stancor would give me an added margin when it gets -40 this winter. I may still try and install it, but will have to make up a mount bracket and 'adjust' the shunt so it fits properly.

Anyway, thanks again for your help. I feel similar in that I've gotten some great advice and assistance from this board & hope I have the opportunity to give some back.

Hawkeye