GEM wiring
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GEM wiring
Ok, I unbolted the 2 screws with the wire blocks from the GEM and removed them from it. I wanted to clean the contacts and also check the ohm reading from the 4x4 switch, can I do that and leave the two blocks unhooked? I guess what I'm saying is if I keep them unhooked just put the key to ACC and then use my ESOF switch to make my selection to check the ohm reading on teh ceartain wires, will that cause issues?
I know the GEM stores codes so if wiring blocks are not on it, will it throw codes and not run properly then?
I dont want to cut wires or put holes in the wires to see the output to the gem, figured having those blocks unhooked would work best.
Thoughts? Suggestions?
Also, are the screws in the top that actually hold the GEM to the fuse banel or is it just clipped in place like in the bottom?
This would be on my 97f150 4x4.
I know the GEM stores codes so if wiring blocks are not on it, will it throw codes and not run properly then?
I dont want to cut wires or put holes in the wires to see the output to the gem, figured having those blocks unhooked would work best.
Thoughts? Suggestions?
Also, are the screws in the top that actually hold the GEM to the fuse banel or is it just clipped in place like in the bottom?
This would be on my 97f150 4x4.
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Well...hhhmmmmmm...ok how to I check down by the gem what it's seeing when I select 4h and 4l and 2h? I was going to use the pin for the blue wire and select 4h and see if I get 1000ohm reading.
I need to rest if the wire from the selector switch to the gem is bad.
Suggestions and tips are welcome.
I need to rest if the wire from the selector switch to the gem is bad.
Suggestions and tips are welcome.
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From: Virginia
I see the selector switch going to the GEM on 2 different connectors, each one has a blue wire. I would unplug the connectors, put one lead of the meter on one blue wire, and put the other lead on the other blue wire. With the meter on ohms, I would move the switch around and see what you get. There are several resistances to be checked. I am assuming you have a factory manual that gives you the correct values?
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yea I saw that as well today....I only saw 2 blue wires and they went into seperate connectors that attacked to the side of the GEM. I thought the same thing like you mentioned but got no readings for them. I know I get a reading for 4L, just not 4H that is why I was checking. Was working to determine if the wire it bad or the GEM.
I took the GEM out and it had no rust or corrosion. It almost seems as it has been replaced at some point. I took the electrical board out of it's plastic cover and looked at everthing, nice and clean.
Any other suggestion on how to check the wire and see if it's bad, either one of them since there are two.
I took the GEM out and it had no rust or corrosion. It almost seems as it has been replaced at some point. I took the electrical board out of it's plastic cover and looked at everthing, nice and clean.
Any other suggestion on how to check the wire and see if it's bad, either one of them since there are two.
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I would just replace both wires, but I dont know witch one is witch on the harness. If I hook them up wrong, I would assume it would mess the GEM up.
Doing that would atleast rule out the wire being bad.
As clean as the GEM is, I wouldn't think it's the problem, but I guess it could be.
I know the plugs that go into the side of the GEM are different sizes, does anyone know witch wire from the back of the switch goes where?
example:
back of switch, pin 2 goes to the smaller harness on the side of GEM
back of switch, pin 3 goes to the larger harness on the side of the GEM
Doing that would atleast rule out the wire being bad.
As clean as the GEM is, I wouldn't think it's the problem, but I guess it could be.
I know the plugs that go into the side of the GEM are different sizes, does anyone know witch wire from the back of the switch goes where?
example:
back of switch, pin 2 goes to the smaller harness on the side of GEM
back of switch, pin 3 goes to the larger harness on the side of the GEM
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From: Virginia
I should have said this before, but the diagram I am using is a 99. But there doesn't seem to be a problem yet.
There is a connector c239, and it has 26 positions for wires. The blue wire in this connector goes to #2 on the switch. This pin is called the "signal return". This blue wire leaves this connector, and goes up to the 4wd switch, but along the way there is a splice into this wire, and this wire also goes to the wiper switch. The wiper switch is the same as the 4wd switch, it has a bunch of resistors to select the correct function. So I think it would be ok to experiment like you are getting ready to do, but if the wipers suddenly do not work, you will know what has happened.
There is a connector c241. This connector has 22 positions, and the blue wire in this connector goes to #3 on the 4wd switch.
There is a connector c239, and it has 26 positions for wires. The blue wire in this connector goes to #2 on the switch. This pin is called the "signal return". This blue wire leaves this connector, and goes up to the 4wd switch, but along the way there is a splice into this wire, and this wire also goes to the wiper switch. The wiper switch is the same as the 4wd switch, it has a bunch of resistors to select the correct function. So I think it would be ok to experiment like you are getting ready to do, but if the wipers suddenly do not work, you will know what has happened.
There is a connector c241. This connector has 22 positions, and the blue wire in this connector goes to #3 on the 4wd switch.
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Thanks Dave,
when you mention pin 2 and 3, is that looking at the back of the switch or looking at it from the front?
If I remove the switch and look at the back of the switch, pins looking at me, from left to right 1,2,3,4 correct? Or should I consider pin 1 being the one on the far left if looking at the actual switch from the front where the selector is?
Not having wipers would be bad. I think mine would be the signal wire bad if anything since the relay is clicking for 4H, figured maybe the GEM is not getting the right signal. (hope that's the case)
Reading over what you said, I'm only going to replace the blue wire for pin3, if I read right, that should carry the signal from the switch to the GEM since the other one is a return signal (signal from GEM to etc..). Correct?
thanks for posting those resistance charts, I'm aware of the ohm resistance I'm looking for.
Thanks again
when you mention pin 2 and 3, is that looking at the back of the switch or looking at it from the front?
If I remove the switch and look at the back of the switch, pins looking at me, from left to right 1,2,3,4 correct? Or should I consider pin 1 being the one on the far left if looking at the actual switch from the front where the selector is?
Not having wipers would be bad. I think mine would be the signal wire bad if anything since the relay is clicking for 4H, figured maybe the GEM is not getting the right signal. (hope that's the case)
Reading over what you said, I'm only going to replace the blue wire for pin3, if I read right, that should carry the signal from the switch to the GEM since the other one is a return signal (signal from GEM to etc..). Correct?
thanks for posting those resistance charts, I'm aware of the ohm resistance I'm looking for.
Thanks again
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From: Virginia
The only thing I can tell from the diagram, is pin 1 is the black wire, 2 and 3 are the blues, and pin 4 is the lightblue/red. Pins 1 and 4 are for the light inside the switch for night illumination.
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Thanks for all the help....here is what I found out. Another member on here sent me part numbers for the GEM. I pulled mine and here is what I found.
I removed the GEM today and was going to test the wires and then replace the one. Well turns out like this:
GEM plastic cover part number- f65f-10170ba
GEM- f75b-14b205-ac had a bar code on the side with a big G and said sport utitlity automatic x4x
Fuse Box - f65b-14a067-af
So I guess this explains why I've had issues with my 4H not working. I have the GEM off of a Expedition/Navigator.
Is there anything engine/transmission related that the GEM controls besides the 4x4 seletions? Asking because I'm debating rather or not to replace the GEM or just pay $40 and get the 4 position switch for the ESOF that the Nav/EXP use.
Thoughts?
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From: Virginia
It controls the buzzers and chimes and warning lights for the seatbelts and the door ajar functions.
The power windows.
The courtesy lights.
The wipers
The 4x4 control
And it's tied with the accessory delay function, that lets the radio and other stuff work with the key off, till you open the door.
The power windows.
The courtesy lights.
The wipers
The 4x4 control
And it's tied with the accessory delay function, that lets the radio and other stuff work with the key off, till you open the door.
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Well today I got a gem from a 2000 f150..... As soon as I put it in and turned the car on the low light came on. It did engage 4h, 4l and 2h just the low light stayed on. I tried all the electronics and the wipers would I only work on max and then were not able to be turned off till u shut the car off. I figured that gem should have worked for. Bad gem perhaps? Can I take that gem to the dealer and have them repgrogram it?Is thAt an option vs purchasing a brand new one?