So I had the typical seized wiper arm on my 2012 which burned out the motor. I cleaned and lubed the shaft and replaced the motor. Hooked everything up and it worked with glass open. Put everything back together and closed glass and it wouldn't work. Opened glass it works. Does that mean the glass hatch switch has gone out? I can pop the glass leaving arm engaged and the motor will turn the wiper. I applied pressure to motor with my hand and it moves fine. Sprayed wd40 in hatch switch to no avail. Thoughts? Thanks for any help, Aaron
2012 rear wiper odd problem
- Thread starter Johan6966
- Start date
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Question: What do you mean by "works with glass open"? When I pop the glass on mine it's no longer connected to the round part that drives the wiper … so it cant work. Also, the round part wont turn with glass popped open. Also … I don't understand "I can pop the glass leaving arm engaged" or "I applied pressure to motor with my hand and it moves fine".
Maybe its just me?
Also - I've had the seized wiper 3 times now (2003 Expy) and it never burned out the motor so I'm wondering if I'm just lucky or maybe there's something else going on here.
Maybe its just me?
Also - I've had the seized wiper 3 times now (2003 Expy) and it never burned out the motor so I'm wondering if I'm just lucky or maybe there's something else going on here.
I see how it can be confusing. Motor (round part) will run with glass opened all the way. If I push/apply pressure to round part it will still rotate, which to me would indicate motor is strong? If I pop the glass but don't open it (leaving arm engaged with motor) the wiper will turn. Close the glass completely and I get nothing.
Something is misaligned and jamming the shaft.
I'd say you should here something from the motor, jammed or not, even if its just a click. To be honest, I'm not very familiar with the physical arrangement of the rear wiper assembly. But, if it works in one physical position but not another, that sorta zeros in on the possible causes. Just investigate what "changes" when you latch the window.
I was thinking that, thinking maybe a connector was on backwards but connectors are usually keyed or something so they cant go on backwards. Or maybe the liftgate glass ajar switch is bad? I tried to look at that circuit on a wiring diagram (2003 Expy) but couldnt figure out anything.
My 2014EL … that round plate will not turn with window popped (not open or fully open) when you activate rear wiper on the steering wheel control
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At the wiper motor connector on the harness side check the resistance between the black/white and a good ground to make sure it is shorted (<5 ohms). Then in the same harness, the white/green wire to ground should measure as an open circuit (>10k ohms) with the glass closed and a short (<5 ohms) to ground with the glass open.
just sayin infant mortality possible, new part arrives broken … ??? just a possibility
been studying the wiring diagram, will take me days to understand it though
probably too small to see blurry & from a 2003
Trainmaster
Old School Member
This design is absolutely absurd. Looks like there's a diode involved with the switch. And where the hell did they hide that?
Is that ohms or volts? Sorry I should have been more clear in my last post. Let's try again.
Before measuring between black/white and white/green we need to make sure that black/white is actually connected to ground. If it is not or has a high resistance that could confuse the computer in the wiper motor assembly and lead to confusing behavior.
With the ignition off, disconnect the wire going to the rear window motor. Set the multimeter to ohms and stick one probe on the black/white wire and stick the other probe on ground. Ideally some spot on the body (these wires run back to the D pillar for chassis ground). For now we can use the black/gray wire as it is also ground. Doing it this way doesn't 100% rule out a problem with the harness, but it can give us some level of confidence. This should measure no more than 5 ohms. If it is more than that it means a bad connection or a break in the wire.
Assuming that is good, with the glass closed you can stick one probe on the black/white and the other probe on the white/green. This should measure as an open circuit (overload) or at least 10k ohms. If that isn't true it means the wiper motor is being told the window is open when it is really closed. That could be caused by an issue with the ajar switch or the wire between the ajar switch and the motor.
Best way to check that is to disconnect the glass latch and then repeat the measurement between black/white and white/green. If it is now an open circuit that means the ajar switch inside the latch is defective and the latch should be replaced. If it is still less than 10k ohms there is a short somewhere in the harness or connector
Before measuring between black/white and white/green we need to make sure that black/white is actually connected to ground. If it is not or has a high resistance that could confuse the computer in the wiper motor assembly and lead to confusing behavior.
With the ignition off, disconnect the wire going to the rear window motor. Set the multimeter to ohms and stick one probe on the black/white wire and stick the other probe on ground. Ideally some spot on the body (these wires run back to the D pillar for chassis ground). For now we can use the black/gray wire as it is also ground. Doing it this way doesn't 100% rule out a problem with the harness, but it can give us some level of confidence. This should measure no more than 5 ohms. If it is more than that it means a bad connection or a break in the wire.
Assuming that is good, with the glass closed you can stick one probe on the black/white and the other probe on the white/green. This should measure as an open circuit (overload) or at least 10k ohms. If that isn't true it means the wiper motor is being told the window is open when it is really closed. That could be caused by an issue with the ajar switch or the wire between the ajar switch and the motor.
Best way to check that is to disconnect the glass latch and then repeat the measurement between black/white and white/green. If it is now an open circuit that means the ajar switch inside the latch is defective and the latch should be replaced. If it is still less than 10k ohms there is a short somewhere in the harness or connector
Well, in an odd turn of events I slaved the old motor in out of curiosity and everything seems to work as it should. It sounds like junk from trying to turn the seized wiper shaft, but is operational. Mrsticker wins! Thanks for all the input turtle. Guess I will return this garbage new one....
