Rear wiper and defroster don't work

The nice thing about factory service manuals is That the may contain the actual routing of the wire harnesses so can see how they are routed and where the plugs are. On later editions you may have to buy the additional body or wiring supplement.

Updates: I was able to test voltage to the harness that connects to the wiper motor and that seems all to be working now. I took apart the new motor and tested the wires and all seemed to be good. When I put it back in to test it started smoking a little bit, which is good cuz it means power is getting to it but bad cuz ya know, smoke. I think it’s just a little bit of grease that got onto a connection somewhere.

An optimist I presume? … lol …

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There’s 3 wires that connect to the motor. Black, ground is good. Brown, constant power getting 12v, good. Blue, intermittent power, not good. I’ve read that it likely means that a relay in the SJB is bad, but that would involve removing it to fix. Is there any way to test that before I do all that? Is it as simple as putting in a new relay or does that mean there’s a larger issue somewhere?

Could be WW motor, internal wiper motor switches, sjb ass’y, or wiper relay problem; or nothing to do then those parts and instead could be a problem from among the ignition switch, lift-gate switches, multi-function switch, or fuse(s). A shop tech referencing the car’s circuit diagrams should be able to tell you which parts are defective, then you could replace on your own if you wanted. That’s probably your best bet.

Some designs of W Wipers, the relays are not separately replaceable, have to replace the entire motor ass’y.

Suggest is you want to try a diy’er diagnosis and repair without shop help, to start by double checking sjb related fuses, and the lift gate switches. Rear wiper motor electronics probably won’t work until lift-gate is up and lift-gate window is closed.