Rear defroster not working this year

Leinhit

TJ Enthusiast
Joined
Sep 26, 2017
Messages
449
Location
MI
2001 sport

I put the hardtop on a few weeks ago and now the weather's turn cold I found my rear defroster is not working.

the rear defroster button just pops back into its original position when I press it and the light in the switch is not working. if I recall correctly when you press the button for rear defrost the button stayed down for about 10 minutes and then it auto turned off.

I suspected the plug where it goes from the wiring harness into the hardtop because the rear wiper was giving me some problems as well.

Last night I pulled the plug out of the hardtop to access it better and was able to plug the wiring harness into it much better and secure than it was. Now the rear wipers are working again.

However the rear defrost is still not.

I checked the fuse behind the glove box and it was okay, I did not find a relay for it under the hood or anywhere else unless it's labeled differently.

is there a relay for the rear defrost I can check somewhere?

Can someone start me in the right direction to finding my problem?

I checked the tabs that plug into the rear defroster on the rear window as well and they are secure.

Thank you
 
I've been having the same issue for about a year. I'll be watching this, as I'm still stumped.
 
is there a relay for the rear defrost I can check somewhere?

this diagram is from another jeep forum and the poster claims it's for a 2001 PDC:
PDClocations.jpg
 
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this diagram is from another jeep forum and the poster claims it's for a 2001 PDC:
View attachment 120870

he also recommended to "pull the horn relay out ( it's exactly the same as the defroster relay ) and plug it into the rear window defogger relay cavity . Then try the button on the dash , it should glow amber if the sytem is operating properly"
Huh, they definitely aren't the same style of relay on mine. What this picture has labeled as the rear window defogger relay is marked as "HBL" on the inside of the cover and has a totally different size + pin config.

Also, dunno if anyone else has this symptom: when i turn on the parking lights and the dash lights, everything is backlit except for the rear defogger, in addition to not having the orange light come one when trying to operate it.
 
Huh, they definitely aren't the same style of relay on mine. What this picture has labeled as the rear window defogger relay is marked as "HBL" on the inside of the cover and has a totally different size + pin config.

The same as my '06. I believe HBL is short for heated back light or heated back window in American :LOL: . I deleted his horn relay recommendation but the HBL relay looks like a standard 5 pin Bosch type relay.

pdc1.jpg

relay1.jpg

relay2.jpg
 
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The same as my '06. I believe HBL is short for heated back light or heated back window in American :LOL: . I deleted his horn relay recommendation but the HBL relay looks like a standard 5 pin Bosch type relay.

View attachment 120875
View attachment 120876
View attachment 120878
I did see in under hood fuse block something labeled HBL but expected it say rear defrost relay. in the owner's manual the fuse behind the glove-box they label fuse for rear defrost relay. So I expected it to be labeled that as well. I will check that and try swapping the horn relay to test it
 
I will check that and try swapping the horn relay to test it.

I think that guy had bad info. It looks like the horn relay is a different size. You'd have to use a relay that looks like this:
relay1-jpg.jpg

relay2-jpg.jpg
 
Have you checked with a voltmeter at the tabs connecting to the defroster to see if any power is actually getting to it yet?
 
I have checked the back of the switch, and I have nothing :( but my fuses are good. so I'm really not sure whats wrong. Dunno if the OP has done the same. Guess I need to trace the wire out for breaks?