Thanks. It still puzzles me why have an intermittent adjustment if there is so little difference in the wipe interval? Seem like they should just have one position without the roller adjustment and let the sensor control the wipe interval. :dunno:

Mercedes does that. 0 = OFF I = rain sencing II = low III = high. Simple! The only poblem is that that darn rain sensor is so sensitive you would end up changing blades every season from them running accross a dry windshield so much;) I just push the button myslef. I have so much wax on the windshild, anything over 30 mph the water just rolls right off:D

Sometime when I use that the serrated dial to adjust the sensitivity
of the rain sensor the interval of the wipe takes off like gang
busters and I have to reduce the adjustment.
So in my view the wipe interval can be quite different.

Sometime the the sensor will notice a drizzle and it will
move a little quicker than necessary. Moving the serrated dial
down to the first position will also cause it to hesitate until
theres enough rain to get it going. At least that's been my
experience. and lately I had a lot of experience with all the storms...;)

One of the things you need to do is to make sure the windscreen around the sensor (behind the rearview mirror) is as clean as you can get it. Wax from some car wash products, and or the use of water repellants like Wynns C Thru can all effect the functioning of the sensor. I normally use a methylated spirits to clean just that area, and I avoid coating it in C Thru.

The adjustment definately changes the sensitivity of the system, so that the wiper will wipe more or less often for a given amount of moisture on the windscreen. The speed of the wiper swipe is not effected, just the interval between wipes.

:iagree: All good info.

I wish it was raining here

On vehicles equipped with AIC or Rain Sensor. There is no intermittant wiper function. The knurled wheel only controls sensitivity. Intermittant wipe function will only work if there is a defect in the rain sensor.