Got a windshield wipers problem someone here will hopefully be able to help with. I have a '92 Cherokee Laredo.

Windshield wipers are completely unreliable now. Sometimes they work, sometimes they don't. When they don't work, when I turn the **** to turn them on, there's a clicking sort of noise from somewhere in the dash that cycles for about 2 seconds, but then the wipers just sit. Then, they might come back 2 weeks later and then die off an hour later. Seems like they're more dead then alive these days.

I've looked at the fuses and they seem fine, though I did have a rain water leak on to the fusebox a while back and that has lead to some weird corrosion issues in the box perhaps. Leak is fixed now at any rate. I've opened the upper hood grill to get at the engine motor. There was a series of holes in the wiper motor cover which lead to me to think maybe the wiper motor was getting wet and dying because it initially seem to be a dry/wet issue (useless bloody wipers in dry weather). But no, fixed the cover with duct table and have had the wiper just die on dry days now too. I did multimeter the electrics to the motor connector, and there was power coming through. This might have been a false positive thing though. Maybe the wipers came back while I had the grill off (this seems to be the case) and tricked me into thinking it wasn't any electrics issue.

Anyways, any help would be appreciated. I know there's just the one fuse for the wipers in the drivers side fusebox under the dash. Is there a relay somewhere I should be checking too?

 

I don't see a relay in the 1990 Cherokee wiring diagram, but 92 could be different?

The problem is likely with the motor unit (motor / park switch?) if there is power in to the motor but it's not turning. Spare wiper motor unit from U-pull salvage yard should be pretty cheap - I would get one of those and swap it in.

 

There is a multifunction switch, a delay module, a fuse, wiring, a motor, and a transmission in play here.
the fuse can be tested with a multimeter for Ohms/continuity. The delay module under the dash on the bottom lip held with hook and loops tape can be tested by by-passing it; plug one end of the wire into the other end.
The motor can be tested by using a multimeter to test the voltage at the leads to the motor's terminals. The thought behind that is if the voltages are correct, then the motor isn't getting the job done.
You can test wires by Ohms/continuity and voltage drop across them.
The multifunction switch is difficult to test without having another switch that you plug in its place.
I can't remember, but I am concerned that covering the holes in the motor with tape could be bad provided that they were for temperature regulation.
Test some of these things and photographs are welcome, then reply with your results.

 

ugh, got this this fixed.

For anyone reading this in the future, it's a fuse issue. I got tricked because the washer fluid spray never stopped worked, UNLESS I took out the main wiper fuse under the dash. So, of course, I figured that the fuse was not the issue for the wipers too. The fuse keeps the spray going, so of course, it's gonna keep the wipers going if they're working properly. NOT TRUE. Today I just replaced the 30 A fuse because **** it I thought and lo and behold, the wipers are working consistently now. In other words, **** Jeep Cherokee electrics, they're ****ing bull****.

 

More like a trainwreck. Flip thru a FSM and you will see just how much of a trainwreck they are. And why.