Rear defrost option

[Freak2189]

did all 2dr's with lift gates come with a rear window defrost? My 93 Yukon has the wireing in the c-pillar but I can't find it in the dash. When I got my truck it had a switch in the glovebox....not installed in the dash.

My rear glass was also replaced with the 2nd gen glass and mine originally had the 1st gen that ran the circuit through the lift struts. I've already relocated the mounts so the glass stays up and sourced the proper wireing to convert the 2nd gen glass to the 1st gen wireing. Just need to know if the circuit is in the dash or am I going to have to call it quits on getting the rear defogger to work.

 

[SunlitComet]

remove the bezel and dig in between the gauge cluster and radio/hvac compartments. you will find several connectors. rpo code zp6 was the installed option with the wiper. rpo code c25 was the wiper system without the rear defroster was the other option. if not original installed it is possible the qire provisions may be in place but are not usually complete to the power source side of the switch. use the diagram below to build the system.

 

[Freak2189]

Thanks for the info. Is the diagram you sent incomplete? It looks to be only half of the diagram

 

[Freak2189]

I do have a rear wiper.... Although I'm chasing down why that doesn't work either. Switch is there as well as the wires

 

[SunlitComet]

how many pages did you look at?

 

[Freak2189]

Sorry I failed to realize that it loaded 2 pages. I have looked & looked and have not found a rear defrost plug. I have noticed that I do have 2 out of the 3 wires plugged into the convenance center. The black/ grey that share a plug and the pink/black. Those 2 are plugged in in the locations it shows but they head off into separate wire looms under the dash. The orange that it shows should be in the lower left is not there and I can't find it under the dash anywhere. Again.... The switch plug is yet to be found either. I'm wish I could look at the RPO codes in the glove box, but mine has been replaced as the bin does not match the dash plate.

 

[Freak2189]

So I'm guessing I can build a harness and just tap into the pre existing wires. Then just run the orange from the switch to the conv. Center.

 

[SunlitComet]

or replace the harness sections without the provisions with those from a donor who has had it.

 

[Freak2189]

Finished the job! Harness was as easy as plugging it in. It's entirely a stand alone harness. As far as conections at the rear....... I had to extend one wire. The chassis is pre wired. 2nd gen glass on a 1st Gen body was no issue at all...... Like I mentioned before. I only had to extend one wire and that was just to reach the body harness conection on the drivers rear pillar.