Rear wiper not working (1 Viewer)

[7nJrX]

As winter nears, it's about time I fix this rear wiper that magically stopped working when I got it back from the shop
The ground is reading 12 v (see picture)


With everything plugged in, when I give the motor ground (with the circuit tester), the motor turns on.
I've pulled out the driver's side back panel on the trunk wall and I see the wire connectors there and I'm aware they're wrapped in loom as they run up to the engine firewall along the floorboard.

Aside from ripping apart the loom and following the wires, I'm hoping there's a less destructive suggestion for next steps. What would you do next to test or resolve?

 

[CruiserTrash]

This might not be the problem, but here you go:

Sometimes the wires for the wiper break at the rear hatch. From inside the cargo panel where you were, they go up the D-pillar, into the headliner, then exit the body, run through a rubber boot, and enter the top of the hatch. From there they run down the side pillar of the hatch and over to the motor. All those wires (rear defrost, wiper, door ajar sensor for the light) get worked back and forth inside the boot and over time break. Might want to check that out.

The rubber thing pops out of the body and there’s some connectors right inside (under the headliner) that you can fish out and disconnect. Then you can slide the rubber boot off and have a look. And yes, the connectors are a real pain to fish out.

 

[RDub]

I had a similar issue on mine. Turned out one of the wires had broken off of a terminal on the wiper switch. Easy solder fix.

 

[7nJrX]

Well this was an interesting one. Thankfully i’ve got smart friends.

Turns out the bottom half of the tailgate was grounded but not the upper rear hatch.

Apparently the shop who did my paint job was too good at their job . The powder coated brackets and bolts appear to be blocking the chassis from grounding the hatch.

Anyways, a quick hack job saved the day for now. Put a ground wire between a bolt in the bottom half (a bolt from the license plate light) to the hatch hinge. This means the upper rear hatch is only grounded when it’s closed. Not the worst thing - but got the wiper moving again.

Learned a lot here about the wiper motor and grounding with the chassis.

 

[CruiserTrash]

@7nJrX good find! Time to check all the rest of your grounds now haha.

 

[N Cascades DsnWrx]

Old thread but also had the same ground issue and no rear defroster or rear wiper function. On the 62 (not sure about pre-88 60 series), there's a bladed connector on the latch inside the hatch behind the pull down handle (see photo's below). Mine is loose and doesn't produce a good chassis ground for the defrost and rear wiper - it is intermittent depending on which way I move it. I didn't see an easy way to better anchor the bladed connector in the latch without removing the entire latch mechanism (maybe sometime in the near future) so I created a short interconnect with a bladed terminal on one end and a round lug on the other. This was tied to one of the mounting bolts to the wiper motor and was what I needed to get a consistent ground. As suspected, neither the defroster or wiper will work with the rear hatch lifted as it needs the contact through the latch to tie to ground so you will need to close the hatch to verify the fix.

Also - tail tale sign for me that it was a ground issue was that my rear wiper did not work but it would turn on the defroster light even when the rear defroster was off. Must be some back flow current happening here. I verified this was the case as this happens with the fix if you turn on the wiper with the rear hatch lifted.