My auto wipers is pissing me off, they would turn on for no reason and not work fast enough when it really does rain. On the sunniest day they would turn on with no fail and the rainest day they would take forever to wipe the tons of water that is blinding my view. Had the dealer update the software but still no improvement anyone else going through this?

BTW: did a search could not find this topic.

 

It could be a bad rain sensor. Take it to the dealer and see what they have to say about this issue. Im sure its an easy fix.

 

That sounds right. They've always worked perfectly on my car.

 

It sounds like you need to have the rain sensor "normalized" by the dealer. This is an almost unknown procedure that is necessary if the windshield is ever replaced, and even if not it usually cures the problem.

Don't be surprised if your dealer hasn't even heard of it before....

 

Taking for granted that the wiper switch is not left in the on/auto position always:

(1) Check for blistering (not common however, can and does happen):

P-B-82.30/399 APR05 – Blistering in the Area of the Rain Light Sensor (RLS)
If blistering is noticed on the inside of the windshield in the area of the gluing surface of the RLS replace the windshield if there is a functional fault. Due to tolerances in the gluing process, peeling may occur on the optical portion of the RLS which may cause the RLS to not trigger with rain present. Bubbles may impair the function of the RLS.

(2) Confirm windshield adaptation:

In addition to updating the software, the RLS should have been coded with SDS for parameterization and windshield adaptation. This is done by reading the original coding from the RLS using SDS; determining windshield tint; removing RLS and replacing with part # A211 870 54 26 (which I believe to be the most recent) if necessary and installing optimized software; then transfer coding using SDS.

(3) It may very well be faulty rain sensor(s) within the RLS there are eight in total.

 

I had a similar problem...Dealer replaced the sensor...Works fine now

 

mine works fine when raining, but the wipers turn on for no reason when the car has been parked in the sun on start up or when driving.
my dealer says it is normal.......did not do it on my 2003?

 

My 06 does the same thing. I think I remember reading in the owners manual that you're supposed to leave the wipers off unless it's raining, then the sensor will set the speed according to how hard it's raining. I found that odd but I haven't done anything about it yet. My wife has a Lexus with rain sensitive wipers and you just leave them on all the time. They work perfectly.