Ford Rear Wiper Motor Harness Wiring Diagram Positive Wire
Joined
·
32 Posts
Discussion Starter · #1 ·
My rear wiper hasn't worked for 2 years. It has been a while since I tried to troubleshoot the issue, but I know the fuse is good. When I apply 12 volts to the motor it works.
Is there a common problem on these that I should look for? I was left thinking it might be the switch itself, but I dunno.
Any help would be sweet. Thanks!
Joined
·
2,201 Posts
When you apply 12v does it go to park when you plug it back in? There should be 12v all the time on the connector to the wiper connector to accomplish the park feature. Have you checked for voltage there?
Joined
·
32 Posts
Discussion Starter · #3 ·
Yes, that is where I found 12 volts. I should have mentioned that. Thanks!
(I mean 12 volts to run the motor)
Joined
·
2,201 Posts
Well, looking at a diagram I found on line, it appears that the relay that controls the rear wiper is a soldered in unit on the SJB.
Joined
·
32 Posts
Discussion Starter · #5 ·
Now that you mention that, I recall seeing that in the schematic as well. I think I may just go pull a wiper control and replace it to see if that works. I've had the SJB apart before, and it would be quite the PITA to work on.
Joined
·
2,201 Posts
I would imagine if you were to find the signal wire from the switch to sjb you could jumper it, probably just a lead to ground, and see if the wiper works before throwing money at it.
Joined
·
14,902 Posts
These units are known to go out. I replaced mine last winter. Do everything you're doing to be sure, but you'll probably just have to get another wiper unit. Not hard to replace
Joined
·
1 Posts
shane06escape said:
Now that you mention that, I recall seeing that in the schematic as well. I think I may just go pull a wiper control and replace it to see if that works. I've had the SJB apart before, and it would be quite the PITA to work on.
A couple of things.
1. No one ever mentions this but it's important. The rear wiper motor won't work or test positive for power (blue wire), if you're working back there and doing all your troubleshooting while the glass hatch is open. I don't know if I'm stating the obvious, but you can do all sorts of testing for power and get ZERO volts if you are doing it while the glass is open. I have seen it a number of times now. It makes one think the problem is with the hard-wired relay in the SJB, but it might not be. MAKE sure you are doing your testing with the hatch fully closed. I've even seen it where you think the hatch is closed, but the contact is not fully tight and so consequently the motor won't run. Just sayin'.
2. If in fact the problem is in the relay in the SJB and you don't want to go to the bother or expense of replacing it (I wouldn't), then there is a simple hack. But remember, it's a hack: Trace the right side rear defroster line to the hidden harness (about 14 inches back from the glass connector). Expose the 4 pin harness by peeling back the protective foam cover. Once you get a good exposure you'll see the metal contact to the wiper motor and the metal contact to the defroster. Simply, using a thin gauge wire, jump the two contacts. Now, when you press DEFROST, you will turn on the wiper motor. Like I said, it's a hack, might be considered shabby but it beats dishing out a few hundred dollars to get a dealer to install and program a new SJB. Some people might recommend cutting the blue line so that it doesn't feed 12V back to the SJB wiper relay, but I'm not concerned about it.
Posted by: dekors02.blogspot.com
Source: https://www.escape-city.com/viewtopic.php?f=8&t=26493