Does anybody have the wiring diagram for an '89? I searched the forum and the diagram that came up in the search the wire colors do not correspond to the wire colors on my GPR. I would like to put a push button on the relay to manually heat the glow plugs.

 

I have a picture of the relay.
I can also tell you what you need to do.
Is that OK?


Wire colors should be;

Out of the engine harness.
Yellow wires from the battery to the relay.
Red wire with green stripe to the ingition switch.
Tan wires from the relay to the glow plugs.

The rest of the wires on the relay come from the controller under the relay.
Black wire is controller ground, usually goes under one of the mounting bolts.
Blue wire goes to a black wire with a pink stripe that goes to the 'Wait to Start" light.
Red wire goes to ignition terminal on the relay.
Green wire goes to the glow plug harness terminal on the relay.
Yellow wire goes to the battery power out of the relay terminal on the relay.

Installation;
Remove the white wire from the relay and tape up the connector.
Connect a 14 AWG wire to that same terminal.
Run the wire through the firewall to a push button switch and connect it to one terminal on the switch.
Be sure to use a grommet to protect the wire where you go through the firewall.
Connect a wire to the other terminal of the push button switch and connect it to a good ground.
You are done with the installation.
Turn the key to ON and push the button, you should hear the relay click.
If you do, congratulations.
If you do not, you may have a bad relay or other wiring problem, post back.

Operation;
Turn the key to ON.
Push the button for 10 seconds when cold, less when warmer.
Start the engine.

 

Thank you for the pic and the info. I will be working on the truck tomorrow. I will let you know how it goes.

 

i olny check in with this board once in a while, but sometimes i think there should be a just glow plugs section.

I also am having troubles.

I had trouble with my relay, replaced it and the trouble continued. I wired a button on the relay and it worked for a while, but than everything quit - no click, no wts light. There definately was power coming in to both the hot side of the relay and to the switch terminal, so power to the unit wasn't the culprit.

I now have replaced the entire control unit and relay (the push button is disconnected and everything is wired up just like Henry Ford intended). Now, when I turn the key on, the wts light flashes on for about half a second and the relay cycles on and off for a couple seconds and than nothing happens. The gp's are about 2 years old and have about 5k miles on them, so unless something unfortunate happened to them, they should be fine.

Any ideas? Do I maybe have a short in my gp's?

Thanks in advance....

 

WesternAuto17,
You need to check the glow plugs.
That is classic burnt out glow plugs symptoms.
Remember they heat to almost white hot temps every time you turn the key ON.

Auto test light with the ground clip on a positive battery terminal.
Remove the connector from each glow plug and touch the tip of the tester to the connector on the glow plug.
If it lights, the plug is good.
If it does not light, replace the plug with a Motorcraft/Beru ZD 9 glow plug.
Don't use those other brands, they are trouble.

 

Thanks for the help, I'll try it.

 

It was the plugs. Thanks for the help.

I'm somewhat competent with gasoline, but these deisels sometimes leave me head scratchin'.

Thanks again.