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I think the cotroller is bad on my 89 F350 w/7.3. But before I buy a new one I want to check the voltage to the controller. Does anyone know which color wire going to the controller is the hot one. All of the GP's ohm out ok and the GP harness ohms ok. I replaced the GP relay but dont have control voltage from the controller to the relay. The wts light stays on for about 15 seconds but no clicking.
https://www.ford-trucks.com/user_gal...oid=72880&.jpg
Check for battery voltage at large terminal marked Battery +
Check for battery voltage at ignition terminal when key is ON.
Check for battery voltage at glow plug terminal while WTS light is ON.
Check for a good ground for the black wire marked ground.
White wire goes negative to energize the relay.
There should be two wires on the ignition terminal when installed in the truck.
The battery + and the glow plug terminals should have the big wires hooked to them.
You should also have voltage at the white wire position when the glow plug WTS light is not on.
Thanks to who ever posted that picture that I used to mark the terminals on. I have been going to take a picture of a late model controller and mark them for a long time, but I just downloaded and edited yours.
Last edited by Dave Sponaugle; Mar 26, 2005 at 12:01 PM.
Thanks Dave the picture helped. I replaced the controller and still have the same prblem. I checked the voltage as you said and it seems to be right. The wts lite comes on with one click and the lite stays on for about 10 seconds and it wont start. If I cycle the wts lite 3-4 times then I here 3clicks and fast wts it will crank. Installed 8 new beru gps, checked the voltage(which I think is right), and checked the harness. Anybody have any ideas?
Just some guesses, since I am fairly new to diesels.
Lift pump
Air leaks
Tired batteries
Slow starter
I'm sure someone else will be along with some better ideas. Good luck with it.
When you replaced the controller did you also replace the relay?
I ask because it is available as a complete unit, relay only or controller only.
A slow spinning starter could cause the problems you are having.
You have to get the glow plugs real hot to easily ignite the fuel so it fires cranking to slow.
Could also be a bad connection at the batteries so the starter is not getting full amperage.
If you look at Dave's picture, remove the white wire from the terminal and tape it up. Run another wire from that terminal to a push button, and from there to a good ground. I usually only use the button in the morning if it is cold. If I have the truck plugged in I don't use it at all. In good weather it should start all day without the gps. They will last a lot longer. If you don't have motorcraft/beru gps, you should change them. If you change them, be careful of the torque (12 lbs.) and use anti sieze on the threads. Good luck with it.
LazyK Idid just like Trike1946 said and it works great. I also installed a small red lite above my pushbutton which is wired on the load side of my gp relay. Thiis way when the relay is giving power to my gp'sthe lite will be on. I figured if the relay sticks or if something happens and the gp's get voltage you would know because then lite would come on. Just something I did and thought I would pass it on.
Thanks for that. Good idea. I am waiting for a new set of G/plugs to arrive. I hope to fit them before doing the wiring alteration so I can use your idea-may just save a set of G/plugs! Thanks again,