Glow Plug Relay Question
Methanoholic
Joined: Mar 2009
Posts: 6,442
Likes: 8
From: Maine (NorCal Native)
Just like you said:
"Then ...
Remove the white wire from the small relay terminal.
Set your VOM for 12v+
Connect the Positive (Red) lead of your VOM to the Positive Battery Post, Not the terminals or any other place, to the Battery Post.
Connect the Negative (Black) lead of your VOM to a Glow Plug Terminal without unplugging the Glow Plug, just slip it up enough to hook up. (It MUST NOT touch the wire connector, only the glow plug terminal or it will not test that connection)
Connect one end of a jumper wire to the small terminal on the relay where the white wire was, Hold the other end safe from ground ...
Turn key on (add ignition power to relay, small terminal opposite of where the white wire was, ie Red Ignition wire).
Now, touch the Jumper wire to ground for no more than 10 seconds ... Take note of the voltage."
"Then ...
Remove the white wire from the small relay terminal.
Set your VOM for 12v+
Connect the Positive (Red) lead of your VOM to the Positive Battery Post, Not the terminals or any other place, to the Battery Post.
Connect the Negative (Black) lead of your VOM to a Glow Plug Terminal without unplugging the Glow Plug, just slip it up enough to hook up. (It MUST NOT touch the wire connector, only the glow plug terminal or it will not test that connection)
Connect one end of a jumper wire to the small terminal on the relay where the white wire was, Hold the other end safe from ground ...
Turn key on (add ignition power to relay, small terminal opposite of where the white wire was, ie Red Ignition wire).
Now, touch the Jumper wire to ground for no more than 10 seconds ... Take note of the voltage."
With the white ground wire from the controller disconnected and everything else connected properly you should have 13V at the large power-in stud on the relay and nowhere else because the power-in wires to the relay are connected directly to the battery through fusible links.
Now turn the key ON and you should have 13V at the small Red/Green wire on the small relay stud opposite from the small stud the white wire connects to. That provides power to the relay coil and to the controller which should now check voltages and decide to turn the glow plugs ON by grounding the relay coil through the small white wire but it can't because you have it disconnected. Hooking a jumper wire from the small stud to ground bypasses the logic of the controller and forces a ground connection, the relay should close and the glow plugs should receive power. If you connect your voltmeter red lead to the large relay stud where the Z bar connects and the black lead to a good ground, then at the instant you ground the relay you should see the voltage on the meter drop to 5-4-3 volts and then continue to drop until it shows about 2.3 volts after 10 seconds. Do not hold the relay to ground for more than 10 seconds.
Now turn the key ON and you should have 13V at the small Red/Green wire on the small relay stud opposite from the small stud the white wire connects to. That provides power to the relay coil and to the controller which should now check voltages and decide to turn the glow plugs ON by grounding the relay coil through the small white wire but it can't because you have it disconnected. Hooking a jumper wire from the small stud to ground bypasses the logic of the controller and forces a ground connection, the relay should close and the glow plugs should receive power. If you connect your voltmeter red lead to the large relay stud where the Z bar connects and the black lead to a good ground, then at the instant you ground the relay you should see the voltage on the meter drop to 5-4-3 volts and then continue to drop until it shows about 2.3 volts after 10 seconds. Do not hold the relay to ground for more than 10 seconds.
How you described to connect, will not produce the results as stated.
That is nothing more then a simple voltage test, a test that is basically pointless other than to see if you are getting voltage.
Connected like you describe, it should start out around 5-6v and climb to around 8-9v.
-Enjoy
fh : )_~
Tuned
Joined: Feb 2006
Posts: 487
Likes: 3
From: Lampasas,TX
Nice cut and paste ... However, I question that, because of
that, that is incorrect ...
How you described to connect, will not produce the results as stated.
That is nothing more then a simple voltage test, a test that is basically pointless other than to see if you are getting voltage.
Connected like you describe, it should start out around 5-6v and climb to around 8-9v.
-Enjoy
fh : )_~
that, that is incorrect ...
How you described to connect, will not produce the results as stated.
That is nothing more then a simple voltage test, a test that is basically pointless other than to see if you are getting voltage.
Connected like you describe, it should start out around 5-6v and climb to around 8-9v.
-Enjoy
fh : )_~
Thread Starter
|
Junior User
Joined: Jul 2016
Posts: 55
Likes: 0
From: Bigfork, Montana
I didn't get to test today awhtx. Other things came up.
Will that test affirm my controller has failed? Or.. By my results from the tests I've done...that the controller is my problem.
I used the PO's push button switch that he used to crank the engine and am using it to heat the plugs. The WTS light stays on 8 or 9 seconds. I hold the button till the light goes out then turn the key and it starts right up.
Will that test affirm my controller has failed? Or.. By my results from the tests I've done...that the controller is my problem.
I used the PO's push button switch that he used to crank the engine and am using it to heat the plugs. The WTS light stays on 8 or 9 seconds. I hold the button till the light goes out then turn the key and it starts right up.
Methanoholic
Joined: Mar 2009
Posts: 6,442
Likes: 8
From: Maine (NorCal Native)
Hmmm, That would indicate the GPC is alive at least ... I would look really close at the white wire especially where it bends into the controller and connects to the relay.
It's acting just like a good controller with the white wire disconnected.
EDIT
Have you tested the GPR to ensure it's a relay and not a starter solenoid/relay. Neither small terminal should have continuity to ground.
-Enjoy
fh : )_~
It's acting just like a good controller with the white wire disconnected.
EDIT
Have you tested the GPR to ensure it's a relay and not a starter solenoid/relay. Neither small terminal should have continuity to ground.
-Enjoy
fh : )_~
Thread Starter
|
Junior User
Joined: Jul 2016
Posts: 55
Likes: 0
From: Bigfork, Montana
I've given the controller a thorough inspection and it looks in great shape. Wires all look good. When I connect the white wire back to its post, get in, turn ignition on, 8-9 seconds the WTS light is on, the light goes out, I turn the key and all it does is crank over. No trying to start nothing.
Yes I checked that right away I received it. No continuity to ground on either small posts.
Yes I checked that right away I received it. No continuity to ground on either small posts.
Methanoholic
Joined: Mar 2009
Posts: 6,442
Likes: 8
From: Maine (NorCal Native)
Dashriprock1977,
Check the ground through the controller ...
Using a incandescent test light ... or a 12v light bulb. LED will not work.
Key off, no power to the the little GPR terminal with the red wires.
Disconnect the white wire, attach a test light to the white wire, then touch the probe to 12v+.
Does it light up?
If it does, then power up the GPC while watching the test light.
Does it get brighter?
Thanks
-Enjoy
fh : )_~
Check the ground through the controller ...
Using a incandescent test light ... or a 12v light bulb. LED will not work.
Key off, no power to the the little GPR terminal with the red wires.
Disconnect the white wire, attach a test light to the white wire, then touch the probe to 12v+.
Does it light up?
If it does, then power up the GPC while watching the test light.
Does it get brighter?
Thanks
-Enjoy
fh : )_~
Methanoholic
Joined: Mar 2009
Posts: 6,442
Likes: 8
From: Maine (NorCal Native)
Sorry awhtx, I missed this or I would have said ...
Eh, no biggie we are all human and we all make mistakes.
-Enjoy
fh : )_~
Eh, no biggie we are all human and we all make mistakes.
-Enjoy
fh : )_~
Thread Starter
|
Junior User
Joined: Jul 2016
Posts: 55
Likes: 0
From: Bigfork, Montana
Dashriprock1977,
Check the ground through the controller ...
Using a incandescent test light ... or a 12v light bulb. LED will not work.
Key off, no power to the the little GPR terminal with the red wires.
Disconnect the white wire, attach a test light to the white wire, then touch the probe to 12v+.
Does it light up?
If it does, then power up the GPC while watching the test light.
Does it get brighter?
Thanks
-Enjoy
fh : )_~
Check the ground through the controller ...
Using a incandescent test light ... or a 12v light bulb. LED will not work.
Key off, no power to the the little GPR terminal with the red wires.
Disconnect the white wire, attach a test light to the white wire, then touch the probe to 12v+.
Does it light up?
If it does, then power up the GPC while watching the test light.
Does it get brighter?
Thanks
-Enjoy
fh : )_~
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Methanoholic
Joined: Mar 2009
Posts: 6,442
Likes: 8
From: Maine (NorCal Native)
That indicates the controller is doing it's job ... Grounding the white wire to turn on the glow plugs!
The Controller is apparently working, you must have another issue!
-Enjoy
fh : )_~
The Controller is apparently working, you must have another issue!
-Enjoy
fh : )_~
Thread Starter
|
Junior User
Joined: Jul 2016
Posts: 55
Likes: 0
From: Bigfork, Montana
When I power up the GPC I still read no voltage on either end of Z bar yet when I hook a wire to the small terminal where the white wire goes (with the white wire disconnected and taped) to a push button switch then to ground the plugs heat up.
If the plugs are good, the harness is good, I have power to the GPC but no power coming out of it...I would think it would be the relay or controller that's messed up.
I don't understand...maybe there's something screwy with the new relay?
If the plugs are good, the harness is good, I have power to the GPC but no power coming out of it...I would think it would be the relay or controller that's messed up.
I don't understand...maybe there's something screwy with the new relay?
Last edited by Dashriprock1977; Aug 5, 2016 at 02:03 AM. Reason: Conversation added
Methanoholic
Joined: Mar 2009
Posts: 6,442
Likes: 8
From: Maine (NorCal Native)
Yea, I know ... That's what is strange!
I just gotta ask to be sure ... You are hooking the white wire back up before trying the GPC.
I don't think it's a screwy GPR, because it works consistently with the GPC bypassed.
My conscious will not allow me to tell you the GPC is bad, but it does appear that way even though it shows it's alive.
You have pulled and replaced the white wire to many times for it to be a bad connection at the GPR terminal.
I gotta admit, I'm a bit stumped! I don't know what to say other than I wish I had that controller in my hands so I could scope it out.
I hate being stumped, to me it's a challenge ... a challenge I must confront!
-Enjoy
fh : )_~
I just gotta ask to be sure ... You are hooking the white wire back up before trying the GPC.
I don't think it's a screwy GPR, because it works consistently with the GPC bypassed.
My conscious will not allow me to tell you the GPC is bad, but it does appear that way even though it shows it's alive.
You have pulled and replaced the white wire to many times for it to be a bad connection at the GPR terminal.
I gotta admit, I'm a bit stumped! I don't know what to say other than I wish I had that controller in my hands so I could scope it out.
I hate being stumped, to me it's a challenge ... a challenge I must confront!
-Enjoy
fh : )_~
Tuned
Joined: Feb 2006
Posts: 487
Likes: 3
From: Lampasas,TX
Drr1977: on my truck I could remove the white wire from the relay and connect a jumper wire from the relay post to ground and "force" the relay to close and the GP's would heat. When I connected the white wire back to the relay and allowed the controller to operate the GP's all I got was click-click-click-click from the relay.
Then I removed the wiring harness from the engine, put heavy-duty shrink wrap on the female GP connectors and reinstalled the harness. Now the controller works just fine.
Obviously there was a problem with the connectors not fitting "snugly" onto the GP's. The bare female connectors were not loose on the GP's to the point that they just fell onto the male posts on the GP's- I had to push them down. But after I put the shrink wrap on the difference in the "tightness" was obvious. And after tightening the fit of the connectors the controller works just fine.
If you want to send me your address in a PM I will mail you enough of the HD shrink wrap to put on your female connectors. Maybe that will fix your problem also.
Then I removed the wiring harness from the engine, put heavy-duty shrink wrap on the female GP connectors and reinstalled the harness. Now the controller works just fine.
Obviously there was a problem with the connectors not fitting "snugly" onto the GP's. The bare female connectors were not loose on the GP's to the point that they just fell onto the male posts on the GP's- I had to push them down. But after I put the shrink wrap on the difference in the "tightness" was obvious. And after tightening the fit of the connectors the controller works just fine.
If you want to send me your address in a PM I will mail you enough of the HD shrink wrap to put on your female connectors. Maybe that will fix your problem also.
Thread Starter
|
Junior User
Joined: Jul 2016
Posts: 55
Likes: 0
From: Bigfork, Montana
When I use a jumper wire to force the relay to close the plugs heat up. When I use the push button switch to force the relay to close the plugs heat up. Both ways the relay clicks once.
If I hook up the white wire to the GPC the relay never clicks.
PM sent. Thank you.
If I hook up the white wire to the GPC the relay never clicks.
PM sent. Thank you.
Methanoholic
Joined: Mar 2009
Posts: 6,442
Likes: 8
From: Maine (NorCal Native)
Drr1977: on my truck I could remove the white wire from the relay and connect a jumper wire from the relay post to ground and "force" the relay to close and the GP's would heat. When I connected the white wire back to the relay and allowed the controller to operate the GP's all I got was click-click-click-click from the relay.
Then I removed the wiring harness from the engine, put heavy-duty shrink wrap on the female GP connectors and reinstalled the harness. Now the controller works just fine.
Obviously there was a problem with the connectors not fitting "snugly" onto the GP's. The bare female connectors were not loose on the GP's to the point that they just fell onto the male posts on the GP's- I had to push them down. But after I put the shrink wrap on the difference in the "tightness" was obvious. And after tightening the fit of the connectors the controller works just fine.
If you want to send me your address in a PM I will mail you enough of the HD shrink wrap to put on your female connectors. Maybe that will fix your problem also.
Then I removed the wiring harness from the engine, put heavy-duty shrink wrap on the female GP connectors and reinstalled the harness. Now the controller works just fine.
Obviously there was a problem with the connectors not fitting "snugly" onto the GP's. The bare female connectors were not loose on the GP's to the point that they just fell onto the male posts on the GP's- I had to push them down. But after I put the shrink wrap on the difference in the "tightness" was obvious. And after tightening the fit of the connectors the controller works just fine.
If you want to send me your address in a PM I will mail you enough of the HD shrink wrap to put on your female connectors. Maybe that will fix your problem also.
Your controller was doing it's job ... His is not!
-Enjoy
fh : )_~