2012 Wiper+Wash goes on by itself

[lopat08865]

Cancelled my diagnostic tom'w w/dealer. Back to CTScott's original plan to replace stalk 1st, then wiper motor if stalk replacement fails to fix [it didn't].

Figuring even w/rain, I can pull washer fuse & still drive w/wiper function. Saw no crimped wiring in engine compartment & way too much to tear-out-to-track-down the wire's full run.

Still thinking it's washer-switch electrical problem since BOTH go on intermittently.

But saw something here saying that switch inside motor fails to show ground at "park" [or bottom] position, so wipers keep moving until it finds it. So let's try that?

Still appreciate any advice on this thread. I will keep it open until solved.

Opened another thread looking for pdf/imagery/video/or just plain advice on how to get at the wiper motor in a 2012 Yaris H/B.

[CTScott]

Originally Posted by lopat08865

Cancelled my diagnostic tom'w w/dealer. Back to CTScott's original plan to replace stalk 1st, then wiper motor if stalk replacement fails to fix [it didn't].

Figuring even w/rain, I can pull washer fuse & still drive w/wiper function. Saw no crimped wiring in engine compartment & way too much to tear-out-to-track-down the wire's full run.

Still thinking it's washer-switch electrical problem since BOTH go on intermittently.

But saw something here saying that switch inside motor fails to show ground at "park" [or bottom] position, so wipers keep moving until it finds it. So let's try that?

Still appreciate any advice on this thread. I will keep it open until solved.

Opened another thread looking for pdf/imagery/video/or just plain advice on how to get at the wiper motor in a 2012 Yaris H/B.

It is very unlikely the motor, as the wiper motor could not cause the washer to spray. If you want to definitely prove that, disconnect the grey wire in the smaller wiper stalk connector, which will prevent the backfeed from the washer motor to the wiper logic. When you do that the wiper will still work, and if the wiper does not pop on by itself you will verify that the problem is between the washer motor and the stalk.

[lopat08865]

Originally Posted by CTScott

It is very unlikely the motor, as the wiper motor could not cause the washer to spray. If you want to definitely prove that, disconnect the grey wire in the smaller wiper stalk connector, which will prevent the backfeed from the washer motor to the wiper logic. When you do that the wiper will still work, and if the wiper does not pop on by itself you will verify that the problem is between the washer motor and the stalk.

Disconnected gray wire & will see if wipers ever come on by themselves. If yes then it's likely wiper motor, if no then likely a fault in the washer motor ground wire?

Disconnect of gray wire killed all washer function. Was hoping to find I could still use stalk to wash, followed by then using stalk a second time to do a wipe. Oh well.

But got me thinking, maybe I could splice in a toggle switch on the grey wire? Then, whenever I needed wash, I could toggle-on and use the stalk for a wash-and-wipe? Otherwise, keep it toggle-off, so I always maintain my access to wiper-only function? Any flaws or potential downsides you envision?

Thanks again, sir, as you saved me at least $107 for a dealer diagnostic, plus expectedly hundreds more for a fix. May ultimately end up surrendering to them for a fix, but in the meantime I have hope that, with your help, I can handle this myself for under $50 :-)

[CTScott]

Originally Posted by lopat08865

Disconnected gray wire & will see if wipers ever come on by themselves. If yes then it's likely wiper motor, if no then likely a fault in the washer motor ground wire?

Disconnect of gray wire killed all washer function. Was hoping to find I could still use stalk to wash, followed by then using stalk a second time to do a wipe. Oh well.

But got me thinking, maybe I could splice in a toggle switch on the grey wire? Then, whenever I needed wash, I could toggle-on and use the stalk for a wash-and-wipe? Otherwise, keep it toggle-off, so I always maintain my access to wiper-only function? Any flaws or potential downsides you envision?

Thanks again, sir, as you saved me at least $107 for a dealer diagnostic, plus expectedly hundreds more for a fix. May ultimately end up surrendering to them for a fix, but in the meantime I have hope that, with your help, I can handle this myself for under $50 :-)

Yes - Removing the grey will disable the washers, but if you want to still be able to use them on demand, until you figure out of the issue is gone with them disconnected, a toggle switch on the grey would do the trick.

[lopat08865]

Originally Posted by CTScott

Yes - Removing the grey will disable the washers, but if you want to still be able to use them on demand, until you figure out of the issue is gone with them disconnected, a toggle switch on the grey would do the trick.

Rainy Monday morning drive to work in the dark makes me think problem *may* still have occurred.

Had the wipers on the whole trip, but after 50 miles driven the yellow "washer empty" light came on. What with the rain & the dark & the wipers going, I couldn't say for sure if the wash came on by itself?