Rain Windshield Sensor
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GLC 300
Rain Windshield Sensor
2018 GLC 300.........Took a major and significant hit to the windshield from a flying 2 x 4 at highway speed. As soon as the windshield was hit the wipers swiped once, as I keep them in the auto sensing mode. I was thinking that the cracks in the glass must be interfering with the rain sensor. But even now, after the windshield was swapped out and I start the vehicle, the wipers will swipe once. The wipers do continue to work as normal but every time the vehicle is started the wipers will swipe only once while in the auto sensing mode. I am now thinking that the hit to the windshield may have compromised the rain sensor .........anyone have any suggestions or ideas - thanks!
Last edited by 8102whtsil; Dec 12, 2023 at 09:10 PM.
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GLC 300
Solved - there was what appeared to be a gel pak that fits between the sensor and windshield .......that pak was somewhat compromised after the impact to the windshield and was causing an obstruction to the sensor ...........easy fix and so far, so good. Just info in case anyone ever encounters this after a windshield impact and/or windshield replacement.
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GLC 300
This was an OEM windshield that was installed ........this little gel pak sits between the windshield and rain sensor to fill that gap. My indy found the gel pak to be compromised which was tricking the sensor into thinking that something was on the windshield and would intermittently wipe while in the auto sensing mode. Easy fix but I don't have any pics that would show this.
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2018 GLC 4MATIC
Originally Posted by 8102whtsil
This was an OEM windshield that was installed ........this little gel pak sits between the windshield and rain sensor to fill that gap. My indy found the gel pak to be compromised which was tricking the sensor into thinking that something was on the windshield and would intermittently wipe while in the auto sensing mode. Easy fix but I don't have any pics that would show this.
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GLC 300
The part was 113. at my local dealer, the gel pak/pad is part of the sensor and is not sold separately. I picked up the cost for that because it was below my insurance deductible and the insurance company stated that would be considered a comprehensive claim. The cost for installation of the windshield around 1000. but that was paid thru my insurance company. Satellite used an OEM windshield but stated they don't replace any sensors as part of their work. After the windshield was installed you could clearly see an air bubble under this gel pak/pad that was obstructing the lens of the sensor. Our windshield took a major hit and suffered some significant damage.
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'21 AMG53 wDPP & ARC, 19 GLC300 - Former-03 C240,2 ML BlueTecs,20 GLE450 E-ABC,15 Cayenne D,17 Macan
Calibration should be part of any windshield replacement.
For the first 3 to 4 years after a new model introduction, there is no aftermarket glass made, so for a little while you don't have to worry about a crap windshield.
I'll pay the difference if any to have a dealer install and calibrate OEM glass.
The last time it was $170 cheaper at the dealer, so I didn't even have to pay the deductible.
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GLC 300
I have one unit that sits in front of the rearview mirror and behind the windshield. That houses the rain sensor as well as what I think is the auto headlight sensor. After impact the wipers started to wipe randomly and I assumed it was because it was sensing cracked glass, the auto headlight sensor never was an issue. No one ever mentioned a calibration that might be needed. Are you referring to a windshield that would need calibration when it comes to lane assist, etc?
