Rear wiper not working anymore. NEW motor worked for a couple days

[new2yukon]

Need to check for voltage, voltage drop, current, etc, at the plug for the rear wiper. Just because it shows voltage, doesnt mean it can carry the current.

You make no mention of what vehicle this is, so I would start by checking the wiring going from the main body of the truck, to the tail gate. Its a rubber flexiboot thing. Thru opening and closing of the trunk, the wires flex, until the break. Have had this happen on a couple vehicles I have owned thru the years.

I'm in a similar situation....but not meaning to hijack this thread.

2001 Yukon 5.3 sle

I get 11.8v or so at the harness. Motor inop. Rear defrost works. The window and gate latches seem to work fine in that voltage stops when those are opened and returns when closed. So those switches seem ok and don't interfere.

Continuity exists from motor housing to rear accessory power so my limited skills say that no ground issue exists.

Washer pumps fluid from the switch but motor is silent. No hum no nothin.

Found only a 25a fuse in engine that is fine. Couldn't find any relays or anything in engine.

New motor doesn't work.

I'm lost. Anyone have thoughts?
Thank you.

 

[Fless]

Have you verified that the rear wiper is parked properly as @Doubeleive suggested to the OP?

 

[Doubeleive]

I'm in a similar situation....but not meaning to hijack this thread.

2001 Yukon 5.3 sle

I get 11.8v or so at the harness. Motor inop. Rear defrost works. The window and gate latches seem to work fine in that voltage stops when those are opened and returns when closed. So those switches seem ok and don't interfere.

Continuity exists from motor housing to rear accessory power so my limited skills say that no ground issue exists.

Washer pumps fluid from the switch but motor is silent. No hum no nothin.

Found only a 25a fuse in engine that is fine. Couldn't find any relays or anything in engine.

New motor doesn't work.

I'm lost. Anyone have thoughts?
Thank you.

no reason a new motor shouldn't work, try removing the wiper arm and have a helper turn the rear wiper on and see if the spindle moves at all, even a smidge. then turn the wiper off and put the wiper arm back on in the parked position.

 

[new2yukon]

Thank you for the replies. It's parked in the retainer piece. I've had the wiper off and everything out when I tried power to the new unit and have since put it all back and wiper is in the retainer and still nothing, regardless of motor. No spindle movement or sound.

 

[Doubeleive]

Thank you for the replies. It's parked in the retainer piece. I've had the wiper off and everything out when I tried power to the new unit and have since put it all back and wiper is in the retainer and still nothing, regardless of motor. No spindle movement or sound.

i bet it is still out of sync if the motor is good, does it move at all if the glass is open?. you have to be cautious with trying that the arm has no mercy, so maybe take the arm off and try it while opening and shutting the glass a few times. Otherwise you might have to take the hatch plastic trim off again and take a look in there and see if you can see what the problem is.

 

[new2yukon]

Ok. I will pull the arm and try that with the glass tomorrow. The panels are off so inside is wide open. Can't see anything wrong but not sure what to look for but don't find melted wires or the like.

Scratch my head how power and ground exists and nothing happens.

Could the IP switch be the culprit? But seems it would be ok since it lets power to the rear harness???...

 

[Doubeleive]

Ok. I will pull the arm and try that with the glass tomorrow. The panels are off so inside is wide open. Can't see anything wrong but not sure what to look for but don't find melted wires or the like.

Scratch my head how power and ground exists and nothing happens.

Could the IP switch be the culprit? But seems it would be ok since it lets power to the rear harness???...

there is a safety switch interlock on that wiper motor/glass hatch, so that it knows if the glass is open or closed so it won't send the wiper arm up to hit you in the face if you open the glass. so the arm has to be parked correctly for that interlock function to work.
i see you might have tested the motor before install? "when I tried power to the new unit"
if so this could have put it out of whack with the hatch glass, so you might try applying power to it and watch it and disconnect power right when it stops to reverse
just guessing on what happened to maybe make it out of sync

 

[new2yukon]

there is a safety switch interlock on that wiper motor/glass hatch, so that it knows if the glass is open or closed so it won't send the wiper arm up to hit you in the face if you open the glass. so the arm has to be parked correctly for that interlock function to work.
i see you might have tested the motor before install? "when I tried power to the new unit"
if so this could have put it out of whack with the hatch glass, so you might try applying power to it and watch it and disconnect power right when it stops to reverse
just guessing on what happened to maybe make it out of sync

Yes, I did hook up the new motor and tried it with just power and not installed and got zero response.

So today I fully installed the new motor and blade is parked in the retainer. No success. Zero response. So I pulled wiper off and still got zero response. And I opened and closed the glass and again zero response.

Can there be power.and have a bad switch on the ip panel? Doubt that but wondering.

 

[Doubeleive]

Yes, I did hook up the new motor and tried it with just power and not installed and got zero response.

So today I fully installed the new motor and blade is parked in the retainer. No success. Zero response. So I pulled wiper off and still got zero response. And I opened and closed the glass and again zero response.

Can there be power.and have a bad switch on the ip panel? Doubt that but wondering.

anything is possible a used wiper switch is like $20 on ebay, I would just hit the junkyard and grab one just to see.
myself I would probably grab another wiper motor also while I was there, just be sure it is off of a 00-02, not sure if they changed those in 03 or not, misc things were changed in 03

 

[new2yukon]

I'm just not looking to throw any more parts money at it until I can rule out the motors. Since both are inop I'm that much more confused. Need to have a known good motor or solid analysis of my motors or I have to take to a shop...which I hate.

Might see if an electrical shop can test for me or give ideas.