ive been dealing with this stupid rear wiper for a while now. Good thing its summer. First problem was it stopped moving and started clicking and buzzing, sometimes randomly on its own while driving with the switch off. anyways, eventually it just didnt do anything anymore so i bought a used motor at a salvage yard (with pulse board), it did the same thing with either pulse board. So I bought a remanufactured motor (using my original pulse board) and now the motor would move but i had to use my hand to help it along or it wouldnt move but maybe a inch or 2 and stop.

with the truck off and the key on the motor will not barely move. with the engine turned on the motor moves as it does in this video. it seems to me there is possibly a voltage problem? alternator...battery...?

in the video, literally, every other wipe is normal, and the other wipes are slow and the motor struggles. consistantly every other wipe alternating good, bad, etc.

VIDEO0008 - YouTube

 

Nice video. My Blazer failed inspection for some things including the rear wiper which had a mind of its own like yours. I have another for parts so I just switched them thinking the other one was OK. It didn't work at all. I took both motors apart and found the erratic one with rusted, but moving gears. The other had no rust inside but the rotor that the blade bolts to was rusted tight. Once I got it freed with PB blaster, it works like a charm. Now to get the washer to work.

Your gears are probably missing teeth in the one shown in your video. You might be able to get the other working if you take it apart and see why it won't move.

 

its a new (reman) motor, i opened it up and it all looked nice and clean, fresh lube, etc

 

Sorry, I didn't read your post carefully enough. Do you have a plug with four wires going into the pulse board from the front? If you pull that off and supply +12 volts to the C terminal (third from left) and ground the A terminal on the left of the pulse board, the wiper should go into the pulse mode. If that works flawlessly, then your wiring/battery/etc is suspect.

You also have another pulse board to try, right?

 

i dont anymore, i returned that motor as defective but i can easily go back up to the salvage yard and get another one, they are cheap there. the auto parts store wont let me return the pulse board if i buy one and it doesnt fix the problem. I will do that test and see what happens

 

i just went to les schwab and had my battery and alternator checked, from the test they can do they said my alternator is fine but my battery is only putting out around 200 cca's. that would explain why it doesnt take hardly any effort to kill my battery with the engine off. ive had the stupid thing die a lot. i wonder if my battery condition has anything to do with the wiper struggling? im doubtful but man i have seen some rediculous things. also, the main concern i have is that the wiper wipes fine, then struggles, then wipes fine, then struggles, back and forth consistently alternating between struggling and wiping fine every other wipe. in the motor where the gears are, its like the arm that rotates along with the wheels on railroad trains. im wondering if 1 position on that arm is harder to move than the other position, and takes more voltage and im not putting out enough voltage for it? i am an abstract thinker and probably way off base here but im totally lost. I will get a new battery and see if anything changes, i need one anyway

 

I'm very interested in what a difference in new battery will do. My battery is weak having been dead and recharged many times.

You had better results when the engine is on vs. off. What about your washer? Does it work under engine on/off and what if any difference it makes on wiper function?

 

My rear wiper moves very slowly if at all unless the glass is wet - I've assumed I need a new wiper blade back there, just haven't bothered changing it yet