Looking for some electrical wizards to help with a problem that i cannot seem to solve; My rear wipers will not run in the "on" position (the normal delay setting) but will run correctly if i push the switch to wash, I have replaced the switch and the wiper motor and there has been no change. Additionally, maybe unrelated, the defrost also does not work.... I have confirmed that the fuses are all intact and have pulled the rubber boot and the hinge point and there is no obvious wire damage where the harness flexes, also, all of the other lights work fine on the rear hatch. Any suggestions?

 

All the other lights?
I suppose all the elements of the defroster could be damaged, seems unlikely though, but would be worth checking continuity or, at least, that there is power to it & the ground is good.

All seems like broken wires to me - & they're not always obvious; a wire can be broken within the insulation. Suggest you identify the supply to the wiper motor, turn it on, open the hatch & wiggle that wire, see what happens.

 

unless I am mistaken, if the wiring was damaged to the wiper motor, then it wouldn’t run on wash?

 

look at the wires again and move them around as suggested.. It's very common for the wires to break/short together and create some interesting situations...Also, check the harness connectors up there and make sure nothing has stretched or disconnected ...You could also pin the connectors at these points to check for power with the switches on...

 

Pretty sure the motor has more than one supply, which would explain why that was so; it certainly has more than 2 wires, but, have to say, I've never figured out the wiring for the motor - or it's switching.

As for "interesting".situations, when I got my latest XJ, opening the liftgate illuminated the tag lights rather than the rear dome light. It was only when I was replacing the liftgate that I found a few damaged wires which I repaired, without knowing what they were for & when I opened the "new" liftgate - the dome light came on as it should. So, yup, anything's possible.

 

In the liftgate there are like 13 wires, none of which are as long as they should be. If you slowly take things apart back there you can cut and splice in about 6inches of extra wire to each wire and fix things. I spent one afternoon doing this. Remember, do just one wire at a time and check things after each wire. After I got done, I made sure I did not have any bare wires and shoved extra wire anyplace it would go

 

There speaks a man with far more patience than I but it's also a good idea to try to stagger the splices, to avoid having a lump in the harness.
Some have suggested separating some of the wires & bringing them through the other, much less busy boot. Makes sense but not sure I could be bothered.