Rear wiper does not work. There’s no movement or sound coming from the rear when I turn it on.
Rear defroster does not work. The light on the switch turns on from the dash.
Rear washer fluid comes out normally.
I recently replaced the wiper motor. The old one was corroded and may have still worked but it was pretty cheap to replace. All the fuses from the engine compartment and the interior seem to be good. My best guess is there’s a bad ground somewhere but I’m just guessing at this point.
That would be my first guess as well. A digital multimeter goes a long way toward diagnosing that. The next guess would be a broken wire inside the rubber gaiter that feeds the harness into the hatch.
Check the contacts of the wiper and defroster for voltage when turned on, then resistance to ground.
With both wiper motor and defroster suddenly not working, first step, double check the fuse(s) that control those circuits are good. A bad ground is possible, but wouldn’t be my first guess, unless ground wire was disturbed during recent WW motor replacement. If the problem is a wiring problem, I’d guess a faulty electrical connector first. Problematic relay after that.
Either the multimeter I have is faulty (it’s a few years old and pretty cheap)or I’m just not using it correctly somehow. I can’t even get a reading to show up when I test the +/- battery terminals. I went ahead and ordered a new one.
I put the dial on ohms and touch the lead. If I get a reading it works fine. You don’t have to pay a lot of money if you are not interested in total accuracy. I think I paid $10 for my last one. Most of the time I’m just trying to get a reading. Don’t care if its 11 volts or twelve as long as something registers.
There’s a lot of flexing in the wires where they go from the body to the hatch, probably at the top next to or with the hinge. It’s often a problem in doors, too. Even if you are lucky enough to find where the wires are broken you still have to at least splice in a new piece of wire or they will break again. Most of the time you end up replacing that whole harness. It’s picky work when you have to get through the trim and the headliner without making a mess.
I removed the wire harness that connects the wiper motor and one side of the defroster, to another connector that’s located in the top back right corner behind a panel and the headliner. The harness looks to be in good condition but I have no idea where that connection leads to yet.
Your hands are really tied without a testing meter. Looking at wires is a waste of time, they can look perfect and be broken or heavily corroded inside the insulation.
I’m guessing the dvm (multimeter) I use for my diy’er auto work cost less than yours, free! … lol … Harbor Freight used to give them away when you made a purchase. I think they are $7 post-Covid, still a good value. If batteries are good, battery connections not corroded, and you turn it on in “volt” mode, you should see it display “0 volts” (or close to that). If it doesn’t display anything, screen looks same on or off, it’s probably a gonner. Time to pony up $7 for a new one.
If it powers up ok, but doesn’t make measurements or are inaccurate/inconsistent
Internal fuse may be blown, take it apart for a look-see
Testing wire(s) may be broken (this is a pretty common problem)
Mode switch may be corroded (another common problem esp w/inexpensive versions). Try rotating it around in circles through all the settings 3 or 4 times.
Google to find a training web-page or u-tube on how to use multi-meter basic functionality. Often the problem isn’t how to use the meter, but how to interpret the results. Requires basic electric-circuit knowledge. Most folks learn this is a classroom, but could be learned by internet training too I suspect.
You can make one in a pinch with a 12v bulb and couple pieces of wire. If the bulb lights you have power. But remember to turn the switch on. Still a ride to hf or the hardware store would be easier.
That advice is for standard quality meters. The $5 ones at Harbor Freight are wiped out if set to the ohms setting and more than about 25V is applied to the leads, or more than a couple Volts is applied across the leads when on the current measurement setting. The last one I opened had a fuse that was hooked up in such a way that it wouldn’t actually do anything.
I ended up getting a Fluke 107 on sale for a decent price. I checked continuity on every single fuse under the hood and also the interior. Also checked as many wire harnesses as I could without removing the headliner yet. I forgot to check voltage leading to the wiper motor but I’ll do that in the morning. I don’t really know what to do next. I’m not getting any issues from any other electrical parts. Local mechanics are going to charge at least $200 to check for electrical issues.
Seems to me you start at the point of failure, the wiper motor, and proceed back until you get a reading. Like said likely frayed wire close to the door.
Spending $200 for a shop diagnosis is probably the way to go. Electrical problems are best diagnosed by referring to the car’s wiring diagram. Otherwise it can be nearly impossible. Imagine you were a tourist driving from Malibu to San Bernardino without a map. The options are to spend the $200 for the shop, or purchase a set of wiring diagrams for you car. The second option would cost considerably less than $200 if a Haynes or Chilton’s repair manual is available for you car. But then you’d still have to obtaining a working DVM & do the diagnosis. $200 to the shop is sounding more and more reasonable.