GPR not shutting off?
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GPR not shutting off?
Need Help!!!!:
Replaced my GPR on the weekend, Now the GPR will not shut off after the engine starts. Basically it is draining the batteries since all juice from the alternator is going into the glow plugs. The voltage on the control wires to the gpr is 12 volts. I thought this should go to 0 within 2 miniutes of the engine starting.
I noticed that as soon as I turn the key the gpr is on, no 1 sec delay or nothing. I'm figuring a short in the wiring hardness. Anybody agree or disagree? What exactly controls the GPR, telling it to shut off? Does anyone have the electical diagrams for this part of the system? I need to start tracing this once down.
thanks
db
Replaced my GPR on the weekend, Now the GPR will not shut off after the engine starts. Basically it is draining the batteries since all juice from the alternator is going into the glow plugs. The voltage on the control wires to the gpr is 12 volts. I thought this should go to 0 within 2 miniutes of the engine starting.
I noticed that as soon as I turn the key the gpr is on, no 1 sec delay or nothing. I'm figuring a short in the wiring hardness. Anybody agree or disagree? What exactly controls the GPR, telling it to shut off? Does anyone have the electical diagrams for this part of the system? I need to start tracing this once down.
thanks
db
Fleet Mechanic
Joined: Oct 2006
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From: Spokane, WA
I don't know much about the gp system, but i do know that in the colder climates my gp's stay on sometimes for over 2 minutes. Never really timed it but have been amazed at how long it has taken amp gauge to recover after start up. Guessing maybe 3 to 4 minutes on mine.
Playing in the Dirt
Joined: Oct 2005
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From: Southwest Georgia
The GPR is control by the PCM, it completes the circuit by grounding. So, on the small terminals, one will have constant power 12V and the other nothing (when checked with a volt meter set on votage). Once you know which one has power, check the other one with a volt meter set on Ohm and ohm it to a ground with the key off (you should have no reading) then turn the key on and Ohm to a ground (you should have a "0" reading while the GPR is activated and then nothing after it shuts down).
When you check for a ground with the key off and you get a "0" reading, you probably have a bad wire or the PCM circuit for the GPR is fried. Let us know what you find.
When you check for a ground with the key off and you get a "0" reading, you probably have a bad wire or the PCM circuit for the GPR is fried. Let us know what you find.
Posting Guru
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From: Ft Scott
Are you 100% sure that you got a GPR and not a starter relay? They look alike BUT the starter relay is grounded through the case and on the GPR the ground is supplied by the PCM. If you do have a starter relay it will do exactly as you described and remain energized.
Hotshot
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From: Western NC
I had the same problem. Mine actually melted the top of the solenoid & the plastic top protector.
I put a starter button on my dash & eliminated the PCM part of the circuit. I wired the starter button into one of the small wires & routed that through the fire wall. Now when I turn the key to the on position, I hold down the starter button for 10 to 30 sec. to activate the glow plugs & then twist the key for the starter & she fires right up.
I bought the starter button on E-bay (30 amp rated) for $10.00 including shipping, even got the button color matched to the interior.
Starter buttons are also known as momentary contact switches.
This is a really easy fix. If anyone wants pics or a more detailed walk through let me know.
I put a starter button on my dash & eliminated the PCM part of the circuit. I wired the starter button into one of the small wires & routed that through the fire wall. Now when I turn the key to the on position, I hold down the starter button for 10 to 30 sec. to activate the glow plugs & then twist the key for the starter & she fires right up.
I bought the starter button on E-bay (30 amp rated) for $10.00 including shipping, even got the button color matched to the interior.
Starter buttons are also known as momentary contact switches.
This is a really easy fix. If anyone wants pics or a more detailed walk through let me know.
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OK, I might of made a mess of things (hanging head in shame). The GPR and Starter Relay are different?
Starter relay is on top of the engine to the right and forward of the fuel filter. Is that correct (1995 f250). If so, I have described the wrong relay in my original post.
From the responses so far, can I assume that this relay never shuts off?
Now the GPR is where? And, does it shut off after 2 min or so. Basically when I disconnected the control wires to the "Starter Relay" my system began charging as one would expect. Plug this relay in and it gets very warm and seems to load down the system to the point that the batteries will slowly drain, even with the alternator charging. Alternator has been replaced and is verified to be good.
Could it be a glow plug gounding out? And How do I test any of these theories short of pulling the valve covers.
Have I made the correct assumptions or am I missing something.
thanks in advance.
db
Starter relay is on top of the engine to the right and forward of the fuel filter. Is that correct (1995 f250). If so, I have described the wrong relay in my original post.
From the responses so far, can I assume that this relay never shuts off?
Now the GPR is where? And, does it shut off after 2 min or so. Basically when I disconnected the control wires to the "Starter Relay" my system began charging as one would expect. Plug this relay in and it gets very warm and seems to load down the system to the point that the batteries will slowly drain, even with the alternator charging. Alternator has been replaced and is verified to be good.
Could it be a glow plug gounding out? And How do I test any of these theories short of pulling the valve covers.
Have I made the correct assumptions or am I missing something.
thanks in advance.
db
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Hay, B Big:
Your solution went though my head as well.
This was for the "starter relay" on top of the engine. Sorry, but I may of got my relay terminology mixed up in my original post.
thanks
db
Your solution went though my head as well.
This was for the "starter relay" on top of the engine. Sorry, but I may of got my relay terminology mixed up in my original post.
thanks
db
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OK, its the GPR relay. That is the one we are talking about. Why was Starter Relay ever brought up to confuse things.
Does anyone have the wiring schematics for this system? Back to my original post are my assumptions correct?
Thanks for the metering suggestions, will do that as soon as I get home tonight.
B Big, did you track this down to the PCM, did it fail slowly, all at once. I'm thinking your mod might be the way to go. Can you forward pictures as you so graciously offered. How was the wiring at the GPR done to effect this mod.
thanks again
db
Does anyone have the wiring schematics for this system? Back to my original post are my assumptions correct?
Thanks for the metering suggestions, will do that as soon as I get home tonight.
B Big, did you track this down to the PCM, did it fail slowly, all at once. I'm thinking your mod might be the way to go. Can you forward pictures as you so graciously offered. How was the wiring at the GPR done to effect this mod.
thanks again
db
Posting Guru
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From: Ft Scott
Because I suspect that you replaced your GPR with a starter relay. You wouldn't be the 1st. They look alike. If you just took your GPR into a parts store and told them you needed one "like this" there's a good chance they gave you the wrong one. Where did you get it, and what's the part number?
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BlueMule: Apologies for my frustration boiling over. I will look at the part number tonight. Unfortunately, I tossed the old one and garbage went out already.
Got the relay from UAP (united automotive parts). Our local Ford dealer decided to close up shop this past weekend, nice timing. So I'm stuck with part store wannabees.
And, may I ask, by insulating the relay from ground will it then work, or is it more fundamental then that.
thanks again
db
Got the relay from UAP (united automotive parts). Our local Ford dealer decided to close up shop this past weekend, nice timing. So I'm stuck with part store wannabees.
And, may I ask, by insulating the relay from ground will it then work, or is it more fundamental then that.
thanks again
db
Postmaster
Joined: Sep 2007
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From: Medford Oregon
Here is a diagram of the federal GPR system in our trucks ...
https://www.ford-trucks.com/forums/a...0&d=1231045998
https://www.ford-trucks.com/forums/a...0&d=1231045998