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Electrical Rear Defrost Relay Location

  • Thread starter Thread starter Mustang5L5
  • Start date Start date Aug 8, 2016

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,231
17,918
224
Massachusetts
Aug 8, 2016
#1
  • Aug 8, 2016
  • #1
I know what it looks like, but where exactly is the rear defrost relay located on an 1988?


I need to troubleshoot mine as my little red light doesn't come on when I hit the switch, and the relay does not click. I have the wiring diagrams, but need to find the relay first to test for power.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,231
17,918
224
Massachusetts
Aug 9, 2016
#2
  • Aug 9, 2016
  • #2
Ok found it.

About 6" to the left of the hood release. It's mounted on the frame by that little tab at bottom. Rotate it 90* and out it comes.




Troubleshot it, and relay is not the issue. Checked for continuity in the defrost switch, and that worked. Traced out wires and checked continuity and all was well. Wasn't til I checked the defrost switch contacts to the plug and discovered two wires in the plug were loose....and swapped! Two middle wires were swapped around.



Swapped them where they should be and taped the harness TIGHT! And now, for the first time in 10+ years. This little red light comes on [emoji41]


Of course, my defrost grid is messed up. Need to score a good rear glass and swap it in, but given that o never drive car in winter, it can wait.


BTW, ford EVTM rocks. If you don't have one yet for your year, get on eBay and grab one




Ps: as for how the wires got swapped...probably me when I installed those white face gauges back in 1998 or so. I certainly didn't have the work ethic I do now.


Sent from my big ass iPhone 6 using Tapatalk
 
Last edited: Aug 10, 2016
Reactions: Shakerhood and jrichker

2000xp8

SN Certified Technician
Aug 8, 2003
8,017
1,614
194
NJ
Aug 10, 2016
#3
  • Aug 10, 2016
  • #3
Mustang5L5 said:
I certainly didn't have the work ethic I do now.
Click to expand...
Ain't that the truth.
When I did the carpet on my carpet I discovered crap i did in like 1994.
Getting it done fast was more important than getting it done right.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,231
17,918
224
Massachusetts
Aug 10, 2016
#4
  • Aug 10, 2016
  • #4
2000xp8 said:
Ain't that the truth.
When I did the carpet on my carpet I discovered crap i did in like 1994.
Getting it done fast was more important than getting it done right.
Click to expand...


Yeah. I've spent some time undoing and redoing things I did as a teenager. Fortunately most of it is reversible. But there are a few things I look at and say "what the hell was I thinking?"

No I'm all about getting it done right


Sent from my big ass iPhone 6 using Tapatalk
 
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