Troubleshooting auto control wipe adjustment

[jcgraff]

Although I have a G90 and my auto control wipe adjustment is working just fine, my son has a 2015 Genesis 3.8 he got recently after his previous 2013 Hyundai Genesis got totaled. The G80 is a nice upgrade, but I noticed recently when riding in the rain with him that the auto control wipe adjustment doesn’t seeem to be sensitive enough to rain. They were very, very slow to start wiping (the windshield was completely covered) regardless of what speed/sensivity was selected for the auto wiper. Even at the fastest setting of what Genesis calls the “speed control knob” the wipers were very slow, like every 10 seconds, to wipe in constant rain, making the auto wipers useless.

I assume that means the sensor in the windshield is not sensing most of the rain on it.

Is there a quick fix or reset for the auto control wipers?

The windshield is clean. I have applied RainX in the past on this car, but I‘ve done so with my G90 as well, and they work fine on my G90.

We don’t know if the windshield has been replaced prior to his purchase of the car.

He just replaced his battery. Otherwise no other recent service or other issues.

By the way, though perhaps unrelated, I know there was an issue with doors not unlocking for passengers discovered right after purchase. He found the issue was correctable online by pulling a circuit breaker for 10 seconds.

I’m hoping there’s a reset for this system that one of you know about. However, it looks like there are several owner’s on this forum having similar issues.

 

[joegr]

The most likely possibility here is that the windshield was replaced with aftermarket. What is the writing on the windshield?
The 2nd possibility is that the sensor is not correctly attached to the windshield.
3rd would be that the LED on the sensor is at or past half-light (sensor needs to be replaced).

The sensor shoots an IR light at the windshield at an angle. There is an IR receiver next to it also at an angle. When the windshield is dry, the light reflects back into the receiver. When a droplet of water is on the windshield over the sensor, it changes the angle of refraction, such that some or all of the light does not hit the receiver. Rain-X can interfere with detection by causing droplets to slide away from the sensor too quickly for it to see them.

There is a sensitivity setting on the inner lever on the stalk. It doesn't do a lot. It alters the timing between sweeps based on the amount of rain the sensor is seeing.

I don't understand the comment about the speed setting not working. The stalk has five settings.
All the way up triggers a manual sweep. The lever returns to the next setting (off) when you release it.
One down from off is the auto setting.
One down from auto is manual low. The wipers run continuously at low speed. Are you saying that isn't working?
One down from low is high. The wiper run continuously at high speed. Is that not working?

 

[jcgraff]

I'll ask my son to look at his windshield and get back with you. Those other possibilities about the sensor not correctly attached or the sensor not working properly is what I suspected, but I'm sure will be costly to repair. Was hoping there was some type of system reset similar to what he found with the electric door locking system.

The Genesis manual calls the switch that allows selection of slow to fast settings when in auto wiping the "speed control knob".

The wiper control switch that allows selection of manual low and high and a single mist wipe is working properly. It is only the auto wipe sensing system that is not working properly.

You said what you call the sensitivity setting and Genesis calls the "speed control knob" doesn't do much. On my G90 it does quite a bit and I'm satisfied with the control it allows.

 

[jcgraff]

The windshield must have been replaced by the previous owner. It doesn't have the Genesis symbol like his other glass.

However, on other vehicles we've had the windshields replaced that have smart wipers, adaptive headlights, etc that all work fine after windshield replacement. They did charge an extra $250 to "calibrate" these items. Not sure what is required, if anything for windshields with sensors behind them.

How does finding out if the windshield has been replaced helps differentiate between an LED sensor failure vs. other possibilities mentioned above?

 

[joegr]

It skews the odds. Some aftermarket windshields are good, and others are not. It wouldn't hurt to pull the cover off and see if the sensor is correctly attached.

 

[jcgraff]

Thanks very much for your recommendations! I'll be visiting him over the next few days and will take a look at it.