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Rear Center Window Defroster..

Zacritz929

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Did you check the ones located behind the rear trim adjacent to c-pillars?
Yes but I didn't go as far removing the seats to look closely but can see that they aren't hanging free. 1 thing that confuses me is with the key on and defroster on my test light(test light grounded to door latch) lights up on either terminal on the center window connector. I was under the impression that 1 terminal would be battery voltage and the other ground. Also my test light lights up very bright on the grid for both windows that don't defrost and lights up dimly for the passenger grid that is still working.
 

HSKR R/T

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Yes but I didn't go as far removing the seats to look closely but can see that they aren't hanging free. 1 thing that confuses me is with the key on and defroster on my test light(test light grounded to door latch) lights up on either terminal on the center window connector. I was under the impression that 1 terminal would be battery voltage and the other ground. Also my test light lights up very bright on the grid for both windows that don't defrost and lights up dimly for the passenger grid that is still working.
Your test light should light up in both terminals as the circuit is complete, and voltage is making the loop
 

Zacritz929

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Your test light should light up in both terminals as the circuit is complete, and voltage is making the loop
Hmm, I want to make sure I'm understanding correctly.. With a test light clipped to a ground, the probe end will light up on either terminal for the center glass? Meaning their is voltage at both wires?

I didn't have the light connected between the 2 terminals at the same time

Where does the defroster grid ground?
 

HSKR R/T

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Hmm, I want to make sure I'm understanding correctly.. With a test light clipped to a ground, the probe end will light up on either terminal for the center glass? Meaning their is voltage at both wires?

I didn't have the light connected between the 2 terminals at the same time

Where does the defroster grid ground?
Your test light becomes the ground. That's kind of how it works.
 

Zacritz929

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Your test light becomes the ground. That's kind of how it works.
Edit:
When using the test light, I have the connector disconnected from the glass

I understand that. I know how a test light works. What Im unsure about is whether 1 of the terminals for the slider defroster connector is a ground and the other is power. If that was the case, the test should not light up when you probe the ground terminal if the other end of the test light is grounded
 
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HSKR R/T

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Edit:
When using the test light, I have the connector disconnected from the glass

I understand that. I know how a test light works. What Im unsure about is whether 1 of the terminals for the slider defroster connector is a ground and the other is power. If that was the case, the test should not light up when you probe the ground terminal if the other end of the test light is grounded
Ahh, I thought your still had the connector attached to the window when you were probing
 

kapinallinen2

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The rear defogger should be a series circuit? Or maybe not, schematic does show just a single resistive element.
C1 (DK BLU/WHT) on the drivers side is the input and C2 (BLK) on passenger side is the ground that terminates at G945A under right side of rear seat. Rear defrost.jpg
 
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Zacritz929

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The rear defogger should be a series circuit? Or maybe not, schematic does show just a single resistive element.
C1 (DK BLU/WHT) on the drivers side is the input and C2 (BLK) on passenger side is the ground that terminates at G945A under right side of rear seat. View attachment 148635
Thanks for the schematic. It is odd that it shows the defroster as 1 element and only shows 2 wires. The driver window has 2 "jumper" harnesses, 1 that goes over to the passenger side and 1 that goes to the slider. I guess they decided to leave that out lol. It's hard for me to understand how 2 of 3 windows don't work yet they all have power and ground.
I guess the circuitry for defroster grids is unique in that way
 

gturtle34

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Where did you find schematic? I have an issue and I think its the main computer or a module that senses the fuel level and dashlights.
 

NewLove

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704554a67a2d67468e6a5bd0de3005a8.jpg

Am I screwed??..


Sent from my iPhone using Tapatalk
 

show723

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Not meaning to resurrect the thread, but thought this could help someone down the line. Found my sliding window element was not working today and quickly figured out why. The black rubber piece referenced in post #4 (connection for the heating grid) had ripped off. What remained on the glass looked like 2 snap buttons like on a jacket.

The connection was dangling behind the driver rear passenger headrest. The webbing tether for securing a child seat located behind that head rest was in the perfect position to snare the connection as the window slid open, and pried it off.

I was able to push the connection back on the slider and recreate the snare first try. I shoved the webbing down behind the seat using a trim tool so it will be out of the way now.

Hope this helps someone down the line.
Thank you for this. Just bought a 2021 Laramie Crew Cab last February and just noticed the rear defrost not working. It's gotta be the tether.

Is the black attachment the only connection to the rear window defrost or do the other 2 windows have one?

Any help would save me a trip to the dealer, greatly appreciated for this newbie to the forums!
 

Zacritz929

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Thank you for this. Just bought a 2021 Laramie Crew Cab last February and just noticed the rear defrost not working. It's gotta be the tether.

Is the black attachment the only connection to the rear window defrost or do the other 2 windows have one?

Any help would save me a trip to the dealer, greatly appreciated for this newbie to the forums!
Each window has its own 2 "button" connector. The side windows connector is tucked behind some plastic trim if I remember correctly. Lower outside corner on each side I believe
 

show723

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Got it, thanks! So if they all have their own 2 button connector and none of my rear window is being defrosted, then it's probably safe to assume it's fuse related maybe? I haven't looked yet, but that'll be my next step.

Also noticing that it doesn't seem like my rear view mirror defroster is working as well.
 

Zacritz929

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Got it, thanks! So if they all have their own 2 button connector and none of my rear window is being defrosted, then it's probably safe to assume it's fuse related maybe? I haven't looked yet, but that'll be my next step.

Also noticing that it doesn't seem like my rear view mirror defroster is working as well.
Could be a fuse or the connector on the driver side has failed. I believe power is fed to this window first and if the connection their is bad then none of the windows will get power to defrost.
 

show723

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Just checked the fuses and they are good, but I think I found the culprit. Just like you said, the connector on the driver side is disconnected. Looks to me like bad engineering, it must have been when I open the middle window, the power sliding glass runs into that area with not much room for error.
 

Zacritz929

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Just checked the fuses and they are good, but I think I found the culprit. Just like you said, the connector on the driver side is disconnected. Looks to me like bad engineering, it must have been when I open the middle window, the power sliding glass runs into that area with not much room for error.
Well glad you found the issue. Their is a special adhesive to glue the buttons back on or you can try to solder them. You'll have to remove your back seats to get to them though
 

show723

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Well glad you found the issue. Their is a special adhesive to glue the buttons back on or you can try to solder them. You'll have to remove your back seats to get to them though
That was my next question. Stopped at Auto Zone and bought this... Screenshot_20231222_200219_Chrome.jpg

But it wasn't for the connectors, only the lines. Any recommendations for conductive adhesives?
 

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