Have a 1994 850 GLT Wagon with the 2.4 non turbo automatic. Today I drove my car to work as usual and the wipers worked fine. I bought some new wiper blades and replaced them during my lunch break and when I turned on the car the wipers did not work anymore.

I checked the fuse under the hood and it was blown. I put another 25 amp fuse in and it blew as well.

Once I got home I took the cover off and removed the wiper motor/transmission. I hooked a jumper from the battery to the motor to see if it worked and it spun freely without issue. It worked on both the fast and normal setting, didn't make any weird noises, etc. I plugged the harness back into the wiper motor and turned the key on and the fuse blew again. This time the wipers rotated partially before stopping and the fuse blowing.

I grabbed an adjustable wrench and rotated it by hand and felt a spot in the rotation where it was "dragging" and had resistance. It makes sense this would blow the fuse since the motor is getting hung up. I removed the wiper transmission from the car again and rotated the motor with the wrench by hand completely unplugged and it rotates just fine when off the car. I again jumped the motor directly to the battery ensure it rotates freely and it did. The motor seems to be working just fine when it gets 12V from the battery. However when it gets 12V from the harness it's acting up. Therefore I don't believe the motor is at fault.

I plugged only the ground harness in (two-wire plug with a black and blue wire) and the resistance was back only in one spot along the rotation. The rest of it was fine. It again blew another fuse (of course).

So it's weird...if the ground is plugged in then the electric wiper motor has a spot where it drags for some reason, but if I unplug it it will spin freely. I don't know why this issue arose right when I changed the wiper blades (coincidence maybe?) but it's winter and I'm going to need them. Has anybody else had a similar issue?

 

Follow up for anyone with the same issue. I went to my local junkyard and pulled the whole wiper transmission with motor attached, plugged it in and it worked fine. So it did end up being the wiper motor even though the motor worked great when hooked directly to the battery.