rkundla

Hi everyone, I haven't been haunting the forums for a long time since my 2009 E350 Sport CPO (bought 11/2011) has been performing like a champ, until recently.

My automatic headlight sensor appeared to get stuck in "night" mode, which caused my car to turn the headlights on all the time when the switch was in auto mode. About two weeks before the sensor crapped out, I had the front low beams replaced when the passenger lamp burned out.

So, since I still have a few months left of my extended MB warranty, I took it to my service dealer (not the same that I bought it from) and asked them to figure out what was wrong with it.

The first call I got back from the service adviser was that the sensor was bad and I would have to pay for a replacement because when my windshield was replaced, it wasn't a MB windshield. Now, a little flashback, when I bought the CPO, there was damage on the windshield and the dealer replaced it for me. They installed PGW Solextra glass - I asked about MB branded, they said it was the same glass as the MB, just PGW branded. Optically it looked fine and they did a great job replacing it, so I was good.

So I told the service adviser that the windshield was replaced when I bought the call over 2 years ago, not recently. That seemed to puzzle her as she went back to the techs and consulted MB and then said they would replace it for free.

I then get a call a day later saying they replaced the sensor and it still did not work. They could not get it 'calibrated' and complained again about the glass. I was getting fed up at this point because she couldn't give me a sound reason for it (it isn't rocket science for goodness sake) and said that I would have to take it up with my purchasing dealer.

So, they kicked the can down the road and I need to get this squared away.

Have any of you seen this problem before? Is the daylight sensor in the rear view mirror our housed with the rain sensing wiper section? Could there be some other issue down the chain causing problems?

Other intermittent issues I have had electrically is with the rain wipers (it will keep wiping when there is no more rain - a switch off and back on of the wiper stalk takes care of that) and the COMAND has spontaneously rebooted itself recently while listening to a MP3 CD. I've also sworn that the C/S transmission switch has automatically switched from S->C, but I cannot with certainty say I didn't knock the console button. I've left it in C since it doesn't really affect my driving.

I appreciate any ideas or comments you have so I can go into the dealer with some ammunition to get this fixed before November! ;-)

Ron

Plutoe

Every time we get a tale of woooo post my stomach goes into knots, because after reading hundreds of this type of post there are always three positions--- the customer, the dealer and then the truth.

I find it hard to believe that an authorized MB dealer would put a non MB part on one of their CPO cars---learning that I would have discussed the issue with MB before purchasing the car!

Never the less the issue is with the faulty rain/light sensor and forgetting about the windshield rouse, within DAS Xentry you can compensate for light sensitivity, but you can't compensate for a sensor failure!!

Did you see a copy of the diagnostic quick test!!

Did you see a copy of the sensor sensitivity test results!

Under the circumstances I would go back to the selling dealership and let them get their ears pinned back by NBUSA!

rkundla

Plutoe, I had already bought the car and while going over it one more time, I noticed the damage to the windshield - it was for all intents and purposes, minor, but I would expect in NE Ohio that the summer/winter cycle would cause a problem, so I asked them to replace it.

I didn't have any expectations that they would pull a fast one on me, since the were pretty straight in their dealings with me up to that point. Their explanation was plausible and my research on the PGW website confirmed they were the OEM of the glass that was originally in the car. So for three years, the sensor worked fine.

The repairing dealer did not share the diagnostic info with me. I didn't press them for it either since there wasn't anything I could do with it.

I will call the dealer I bought it from and have them fix it under warranty. If that means they need to replace my windshield because they violated the CPO terms, then so be it.

However, do you know specifically where that sensor is on the 2009 W211? Is it in that sensor mounted directly to the windshield behind the rear view mirror? I'd like to be able to know that before I go into the other dealer so I can be able to participate in the discussion.

Plutoe

You are correct the rain/light sensor is glued to the windshield and is located behind the rear view mirror!!

The only thing I would say is ---show me a copy of the DAS Xentry quick test results---and take a picture of the clerks expression while doing so!!