I was driving to work today and i hit a large pothole and my lights flickered and the truck died, i got out and popped the hood to see what was going on.

I checked for power at the fuel shutoff solinoid on the ip and no power, so i had no power to my fuel pump either as the relay is activated by my 12 volts at the shutoff solinoid.

I started wiggling wires and i was randomly getting the wires to connect as i could hear all my relays clicking on and off (the fuel pump, the shut off solinoid and the glow plug relay)

I saw a wire was hanging out of the eletrical tape around my fuel pump relay so I unwrapped all of it and temorarily reattached the wire.
I tried again and still wasnt getting any power to the same three things, ip, fuel pump, and glow plugs.

At this point i was getting late for work so i found a wire in my truck and jumped the prong that the loose wire came off of the fuel pump relay, which also gave power to my fuel shut off solenoid, now for some strange reason my glow plug relay would do its thing everytime i attached or reattached my jumper wire?

Whats up with that?


So after work i rewired my fuel pump relay and i tightened down my starter solinoid connections and all my battery connections (they were a little loose, i could wiggle em a little bit)

Turned the keys over and...... No wts light.

So i jumped the relay again and my wts light comes on again and my glow plugs come on again, WHY ARE MY GLOW PLUGS BEING POWERED FROM JUMPING MY FUEL PUMP RELAY?!?!?!? I dont think they should be! Should they?

At least i can still get the truck to run for now, but id like for my truck to shut off when i take the keys out, lol

 

U guys nervous to touch this one? Lol

 

Ok. Things are always wierd when:
1. You haven't experienced them before.
2. You may be unfamiliar with a system.
3. They are beyond current knowledge.

Ok. There are stickies on glow plugs and systems. Worth reading. Research thoroughly. The elements that should interest you are points on grounds, connections, types of solenoids, fusible links, GP controllers.
Next, is your wiring factory, or has someone else altered it?
Establish your problem more closely if you can, and I'm sure there will be knowledge shared with you to help.

 

Ive read the stickies already i do t think they will really help me here as im having problems with multiple things other then the glow plugs, i know how the glow plugs work ive done it all before.


i did some reading yesterday and now im at the understanding that the twelve volts that supplies my fss is off the same wire that triggers the glow plug relay? And that is why when i run 12v hot to my fuel pump relay it is in turn giving my fss 12 volts and also triggering my glow plugs to cycle,(it is not keeping them on continuously it is just triggering the cycle as if i turned the key forward.

To answer your question, all the wires for my gps are in the stock configuration, altho they have been replaced with new wire, but that was a year ago and i know it was wired correctly. My fss power wire is completely stock, my fuel oump relay wires are not stock(obviously) but are wires properly from what i read off of the mod thread, and has also been wires for over a year with no problems.

My question is, all the wires on the hot side of the starter solinoid have 12v at all times correct? So what is it that triggers all my accesories to turn on when i put it in run? As of now everything works perfect including cranking, im just not getting power to trigger the gps, thw fuel pump or the fss. They must be relAted.

I am going to try and find a wiring diagram for this truck by the weekend, until then any advice u can give me is greatly appreciated

 

The ignition switch. First thing to check.

 

So since all my accesories work 100% and my truck cranks like it should and everything else, i can rule out a bad ignition switch?
The only thing i dont get power too when i go to the run position is the gp relay, and the fss which in turn doesnt trigger my fuel pump relay.

Everything else works PERFECT with my keys in the run position,

 

If you're not getting power to the FSS, then you can't rule out the ignition switch. I don't have the EVTM in front of me, but the switch has multiple make/break contacts for the RUN position. The circuit for the FSS may use different contacts than the circuit(s) for the accessories.

 

Ok thanks for the response.
Is it normal for ign switch to just die like that? Or do they usually start to wear out and act up before they crap out?

 

It could fail in either way. Even if it's a gradual failure, often with electrical items, it'll work without any indication of trouble as it's wearing / approaching failure. Then it crosses the "threshold" failure point, and appears to fail all at once, when in fact it was approaching failure for some time.

 

I found the wire that got pulled out, it was right in the connection beside where the glow plug wires are known to melt at the connection, i wired around the connection and sauldered the wire, i know have power to my fss and my fuel oump is working again.

Altho i am still not getting my glow plugs to work, the wire i found ThT i reconnected has continuity to the trigger wire on my glow plug relay. However my relay isnt drawing in and is not working, i am wondering if ibhad maybe screwed uo the gp relay when i had the truck hot wired?

When i hot wired it all i did was run a wire off the + side of the battery to my trigger terminal on my fuel pump relay, my fuek pump relay is usually triggered by the 12v at the injector pump. So when i hot wired it i had power to my fss also, and since my fss and my glow plug relay trigger wire is the same wire that powers the fss, my glow okugs woukd cycle. But i am 99% sure that i didnt have my gps on the whome time. Bexause my wts light was working normally and the truck would start right up.

How can i test my gp relay?

 

I think ive narrowed it down to my gp relay, i have twelve volts on the power supply side of my relay, (the two big wires) and when i turn my keys i get 12v to the small red wire (trigger side im guessing).
But after i turn the keys and i get the 12v to the trigger wire i dont get any power to the side that the squiggly thing is on, so im concluding that its the relay? Am i correct here?

I checked the ground wire for the gp comp and it had zero resistance to battery ground so its good

 

Take the small wires off your GP relay and test it. You need B+ to one terminal, and ground to the other. See where the white wire from the GP controller went. That's where you need to ground the relay to make it turn on.

This should at least tell you if it's the relay or the controller underneath.

 

So i need to run power to the terminal tht the red wire was on? And then ground the other small terminal out?

 

I jumped power to the small terminal with the red wire then ran ground to the other small terminal and the relay woukd buzz but not click..... Good or bad?

 

Can some one answrt this question? I need to know before the end of the day so i know if i need a new relay or not