Was having an issue with my front wipers coming on when the car starts and also spraying windshield washer fluid on the TB. Thought maybe a dodgy multifunction switch. Popped a new one in and same issue. Determined the wiper motor is at fault. Part ordered and I pulled the old one out ready for the new part. Hope it doesn’t rain anytime soon!
Washer and wipers turn on when truck started
- Thread starter krunal88
- Start date
While I don't have a good answer for you about this problem, there is a chance a member has had this happen and knows what it is. That saves you from shooting the "parts cannon" and wasting money. If you post here first, a member may be able to help or at least look at you tube for guidance. Be careful at Y/T. Lots of crap videos and crap info there.
Not a common issue. Only one thread I found that's remotely similar:
Doesn't mention the washer though. To me, it sounds like it's something in the circuit triggering the washer and then the wiper initiates the wipe as it should after the washer. The washer relay control is in the wiper motor so a defective wiper motor control board is entirely possible.
Doesn't mention the washer though. To me, it sounds like it's something in the circuit triggering the washer and then the wiper initiates the wipe as it should after the washer. The washer relay control is in the wiper motor so a defective wiper motor control board is entirely possible.
How did you do this? My guess is that you have a dodgy wash relay and not a motor issue... maybe although it looks like the motor module does have a big part and the washer would likely run continuously if it was the relay... :-( Of course, changing the motor out does NOT exempt the wiring.
You could do some measurement on a few of the incoming signals at the motor connector to confirm... but since you got the motor already coming, time will tell I guess... hope it solves the problem.
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I didn’t do a lot of diagnosing on my end. Thought the multifunction switch would be the easiest attempt and for $22 off Amazon it was worth a shot. My old switch had all the lettering on it rub away from use so it was a useful upgrade. When that didn’t work, I swapped in some new fuses and did the relay swap as well to no avail. I saw a forum post mentioning that the washer function is tied to the wiper motor and there is a control board on it that can go bad. The wiper speed was constant when activating wipers with no speed variation up until the fastest setting and also triggered the wash nozzles randomly to stay on continuously. With the wiper motor out, my front windshield wash pump will not activate, the rear works fine. Couldn’t find the control board on its own, so just bought a new unit.
There are three connection coming from the turn stock. One is for high and one to produce the variable speed indication / mist. That control line is somewhat "resistive intense"... meaning dependent on the resistance to determine what action should happen.
Did the symptoms change at all when you switched out the signal arm... ie. did you get any difference in speeds?
One more question... what year of truck do you have and do you have a "mist sensor" feature?... not sure when that feature is enabled but it shows ups in the circuit.
The symptoms did not change at all when I swapped out the signal arm. The speeds were the same up until the highest setting where it would speed up. Seems like the pulse function was not working. That leads me to believe the multifunction switch was operating as normal. I have a 2005 Trailblazer. No mist sensor that I know of. Is that a rain sensing function?
I think so... I don't have the feature on my 2008..... but the feature does appear to have potential input in the motor module..... BUT there are some "strange things" that happen with respect to that sensor. They appear to occur at run / accessory...
You might check to see if you have that feature.
That sensor, if you have it, would be a round optical sensor on the windshield directly in front of the rear view mirror.
It's a fairly rare option, mostly seen on very early years. Even my fully optioned '02 EXT LTZ or '06 9-7x didn't have it. IIRC, my '08 Avalanche had them but I hated the irregular wiping so I disconnected the sensor. They would work as normal intermittent wipers.
It's a fairly rare option, mostly seen on very early years. Even my fully optioned '02 EXT LTZ or '06 9-7x didn't have it. IIRC, my '08 Avalanche had them but I hated the irregular wiping so I disconnected the sensor. They would work as normal intermittent wipers.
Matt
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- Dec 2, 2011
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My 02 LTZ had the rain sense wipers and they had a grease issue. Grease would get onto the copper conductive ring in the motor assembly and it would cause the wipers to chatter or stutter as the wiped.
The solution when it happened was to take the motor out, remove the housing and wipe the ring clean, reassemble and wait about 2 years for it to happen again.
The solution when it happened was to take the motor out, remove the housing and wipe the ring clean, reassemble and wait about 2 years for it to happen again.