Location of the glow plug control card on a CUCV

[CSFJ]

I know a few of you guys have the m1008 CUCV trucks. Hopefully, someone can get a pic of where the GP control card is supposed to be mounted. I'm trying to put mine back together, after a PO converted the plugs to run off of a push button. They left the temp switch, and relay in my truck, but apparently removed anything that had to do with the control card. I'm trying to figure out a) what the part looks like, and b) where it is in relation to everything else.

 

[1987 GMC Jimmy]

I wish I could be more help, but from what I could dig up, it mounts under the dash by the steering column. Pictures appear to be nonexistent so hopefully one of the guys on here can deliver. Here, however, is a picture of the actual controller.

You must be registered for see images attach

 

[CSFJ]

I wish I could be more help, but from what I could dig up, it mounts under the dash by the steering column. Pictures appear to be nonexistent so hopefully one of the guys on here can deliver. Here, however, is a picture of the actual controller.

You must be registered for see images attach

I've seen that pic in my searches too. The problem I'm running into, is that the actual glow plug card, the portion that's replaceable, is a circuit board that appears to plug into what I can only imagine is some sort of case or housing. Unless I've got the scale of the thing all wrong, and it fits inside that. You're definitely right about the pictures being nonexistent, seems as though that's the one piece no one ever photographed. This is what is sold as a replacement for the inop ones

You must be registered for see images attach

 

[CSFJ]

I wish I could be more help, but from what I could dig up, it mounts under the dash by the steering column. Pictures appear to be nonexistent so hopefully one of the guys on here can deliver. Here, however, is a picture of the actual controller.

You must be registered for see images attach

I decided to take another look under the dash again, and this time pulled the cover off this

You must be registered for see images attach

Lo and behold, looky what it revealed

You must be registered for see images attach

I guess I should have been a little more inquisitive about what the box zip tied to the column was. Could have saved myself some head scratching. I don't know what made me think it would be underhood, but that's where I kept thinking it should be. I guess the next mystery is what, if anything was attached to this?

You must be registered for see images attach

The blue wire holds that position as if it used to be plugged into something there. All that's left are the holes in inner fender.

 

[1987 GMC Jimmy]

Hmm... My guess was that the card would be inside the module, but that didn't add up because the labeling on the stock photo you posted of the card didn't match the pinout diagram of the controller. So you don't need a module, then, and you just need to wire to the card? In my readings, I saw something about the glow plugs staying on and burning out if something sticks in the relay or the controller. I'm sure you saw that, too, but I guess your only option is to restore the factory setup or do like the PO did and switch them on manually.

 

[CSFJ]

Hmm... My guess was that the card would be inside the module, but that didn't add up because the labeling on the stock photo you posted of the card didn't match the pinout diagram of the controller. So you don't need a module, then, and you just need to wire to the card? In my readings, I saw something about the glow plugs staying on and burning out if something sticks in the relay or the controller. I'm sure you saw that, too, but I guess your only option is to restore the factory setup or do like the PO did and switch them on manually.

I'm going to take it back to factory for the time being. Now that I found the spot under the dash for the circuit board. The only mystery left is that blue wire now. It is part of the glowplug harness, but not sure what. I've got the schematic for the circuit, and the only light blue wire listed is the negative control for the glow plug solenoid. It shows no splices or lists no other light blue wire. I guess it must be for diag of some sort.

 

[Honky Kong jr]

You could build your own using a timer and a temp sensor.

 

[CSFJ]

You could build your own using a timer and a temp sensor.

The way the factory designed it, the controller looks at the coolant temp in the block, and re-fires the glow plugs as needed in decreasing increments. I'm guessing that the original issue with the system had to do with the connection at the cts. The wires coming out of the harness plug at the sensor were frayed, and corroded, as though it had been that way for some time. I've got the new sensor and pigtail ordered, should be here Tuesday. I've already got a new solenoid/relay sitting on the bench, so if the cts doesn't fix the system, I'll order a new control card.

 

[Honky Kong jr]

The way the factory designed it, the controller looks at the coolant temp in the block, and re-fires the glow plugs as needed in decreasing increments. I'm guessing that the original issue with the system had to do with the connection at the cts. The wires coming out of the harness plug at the sensor were frayed, and corroded, as though it had been that way for some time. I've got the new sensor and pigtail ordered, should be here Tuesday. I've already got a new solenoid/relay sitting on the bench, so if the cts doesn't fix the system, I'll order a new control card.

Gotcha. I would have probably put Tandem VW glow plug relays in one for each bank with an OE temp sensor. But that's me and I just do **** like that. Lol Working on VW and Audi cars for 22+ years you learn how to bypass thier stupidity and how thier control systems operate.

 

[CSFJ]

Gotcha. I would have probably put Tandem VW glow plug relays in one for each bank with an OE temp sensor. But that's me and I just do **** like that. Lol Working on VW and Audi cars for 22+ years you learn how to bypass thier stupidity and how thier control systems operate.

lol. It's been funny working on this. When I first brought it home, the wiring seemed daunting, but I learn more about it nearly every day. Now I can see past all the extra BS wires added for "repairs" and the system gets more simplified each time I look at it.