drb930

I hate those rain sensor wipers.
Always too much.
Give me a good intermittent wiper like GM makes.

acr2001

Some info from my own experience with the rain sensor in my 05 W203:

The wipers DO wipe over the rain sensor. This is absolutely necessary. If your blades don't wipe over the rain sensor area then you will wind up with the wipers at full speed for any rain.
The reason for this is because the system determines how often to wipe the windshield based on how long before water builds back up between wipes.
If the area above the rain sensor is dirty or smudged you will also have the problem described because the system thinks it's still wet even after it just wiped. If the outside of the windshield is fogging up for any reason (as sometimes happens) the wipers will also work faster than they should, same reason.

I use a chemical windshield cleaner to strip the glass every so often (maybe twice a year) and then I rain-x the entire windshield including the area over the sensor.

Unless the outside of the windshield fogs up my rain sensor works perfectly all the time - it's always set to auto. It definitely does not run the wipers too fast. If anything, it waits until there is a good amount of water collected on the glass before triggering a wipe. I suggest you clean and polish the area of the glass around the rain sensor, then apply some rain-x. Works for me. I think proper application of the rain-x over the sensor area will slow down the wipers if anything because the water beads, taking up less surface area on the windshield. That should fool the sensor into thinking there is less water accumulated on the glass. When your car had a brand new windshield (the conditions the rain sensor was designed to work perfectly under) the water probably beaded up the same way it does after an application of rain-x.

Glyn M Ruck

Ah! - Thanks acr2001 - This all makes total sense. I thought he might have the wrong size wiper blades fitted - many on the forum seem to have moved away from stock - I measured mine for someone a while back but I'm RHD. Both 20 inch I seem to remember. Some seem to have staggered 20" & 22" & a variety of others.

LILBENZ - get longer blades

LILBENZ230

Okay I was away from the car earlier and now that I've been back in it yes the wipers wipe across the sensor. They are factory SWF models 20" both sides.

I cleaned the windshield and cleaned the wipers but they smear water around and the sensor keeps speeding them up. I think that the smearing the wipers are doing is making the sensor think that there is more water than there really is.

So I guess this answers the question I originally posed! If your wipers are smearing water over the rain sensor rather than clearing it, it will cause them to run too fast. That's my problem and it should be fixed with new wipers that actually do their job. I'll report back!

Thanks everyone for your input, especially thanks to you, Glyn, for your documents that confirmed the theory I had.

Moviela

I would suggest against Coke in the US because unlike South Africa which uses cane sugar, America uses cheaper corn syrup. You don't want to goop up the works with it. It will attract insects that will build "houses" and block the drains.

Most manufacturers and glass companies suggest a product made from egg shells called Bon-Ami. It is a white powder for cleaning kitchen and bath surfaces. It is a mild abrasive, but will not scratch glass. Sprinkle on wet glass and use a clean sponge to work it into a slurry to clean the glass fully. Oh, resist the urge to use Dawn dish soap, unless you car was painted by Wedgwood, Lenox, or Mikasa.

If you want to use Rain-X, keep in mind it is an emulsion product. After application, the liquid must dry to a haze, then be completely removed by buffing. It forms a smooth layer over the comparatively rougher surface of the glass. This allows the water to slip right off.

Glyn M Ruck

Hey - Good point - Diet Coke, Coke Zero or whatever. We use it all the time. It's the mild Phosphoric I was looking for.

Heed Moviela's comment - good local knowledge - Coke is not Coke the world over. The variation in taste from market to market is enough to tell you that. Man I've drunk a lot of Coke in my global job trying to stay away from defiled water & Delhi belly.

LILBENZ230

I'm addicted to Coke! I just don't think I want to use it on my windshield. I cleaned the windshield today, but it's not supposed to rain for another week so I may have the new blades in by then. We shall see.

Glyn M Ruck

Love the edit - Yes - that would be expensive white powder to make the slurry that Moviela talks of.

LILBENZ230

I've attached a picture to help explain. I have noticed that both of my front rotors have this odd characteristic. See in the pictures how around the outside maybe half-inch of the rotor is a different color than the rest of it? It looks almost like the pads aren't making contact with that part of the rotor.

The dealer I bought it from did the brake job as a condition of purchase since they were worn out already. Is it possible they could have installed them incorrectly or used the wrong size pad? No errors in the dash and no funny noises or vibrations are present. Just both front rotors have that different colored ring around them outside of the surface.

LILBENZ230

Bump - any ideas?

Glyn M Ruck

The photo is indistinct but is the pad actually contacting the outer ring? Looks like the dealer did not replace the rotors but had them ground & incorrectly at that. Pull a wheel & measure the rotor thickness. Splinter posted the condemning limits recently. Sooner or later the pad will wear so you have even contact but it's less than ideal.

LILBENZ230

It doesn't look like the pad on either side is contacting that outer ring. I can't figure out why it would be a different color if it was making contact. The brakes seem fine, they don't make noise or cause vibrations. They're about 18,000 miles old at this point and I'll probably just have this corrected when they're worn out. Actually I suppose I could put a dot on the rotor's outer ring with a marker and see if the pad scrubs it off or not. Would that be a safe test? I'm not very mechanically inclined! LOL

Glyn you're such a huge asset on here. Thanks for all the times you've already helped me.

Glyn M Ruck

Yes - Good thought - That would tell you if it was touching - It would not tell you whether it was touching at the same pressure as the inside ring but I would not be too concerned. If the brakes feel adequate & there are no vibrations I would not loose sleep. When I was posted to Australia by my company I had a 3.8 litre Holden Berlina as a company car. The rear brake discs (rotors) showed what you are seeing but in reverse. My ring was in the centre. I complained at the cars first service & the Aussie service manager said to me - " Don't worry mate - Holden never machine their discs properly - It'll wear in!" - and it did. Just keep an eye open for cracks in the rotors - sometimes you don't feel it in the early stages but brake dust increases alarmingly on one wheel.

I don't think you have anything to worry about.

LILBENZ230

The pad did scrub my marker dots off. So it is making contact. Perhaps just not at the same pressure. Thanks for your help!

Glyn M Ruck

Yeah! Just drive it. Funilly enough it's probably a good sign that it's the same on both sides - Good Luck

LILBENZ230

Recently I requested the service history on my car prior to my purchasing it. I was denied, saying that I could not have access to that information. I was completely taken by surprise, so I asked around at another dealer and kept getting the same "privacy" story as a reason they can't release my records. None of this makes sense to me. I am not asking who owned the car previously. They can take that information out. All I want is the records of service from before I bought it. And if these dealers were so concerned with the privacy of others, they would make sure the loaner paperwork is removed from the loaner cars after each time it is returned. In my current loaner, there are 3 old slips listing people's names, addresses, and credit card numbers.

Can anyone confirm that Mercedes service records are subject to HIPPA the same as a person's medical records?

splinter

That's horse puckey.

Asked my SA for a VMI as part of a PPI that was, not coincidentally, conducted elsewhere.

He said “no problem” and invited me back for service and warranty work. It lists the former owner’s last name which, of course, I already knew. He has received a bottle of a quality California wine at Christmas every year hence and taken care of several goodwill (expired) warranty repairs. Sometimes, it’s who you know and how you ask.

Medical or credit records and a vehicle’s service/warranty history should hardly be afforded the same level of privacy, IMHO.

LILBENZ230

Well that's the line I get. They act as if it is extremely confidential. Any suggestions on what I should do to get it? I have asked dealers in my area and they all say the same thing.

UK-C200

Only thing I can suggest is to give MBUSA a call - I've never purchased a car without know the full service history - from the dealer...

C230 Sport Coup

Hmmm....my GF was looking at a used ML at the dealer, the guy faxed me the whole history of the car, including the oring being replaced in the tranny, and 1 quart of fluid added.

Of course, she went off on her own, and bought something else.
(and now bi*tches it doesn't have the options she wanted..)

HIIPA is federal law, and doesn't include personal transpo, FYI.

moonrkr23

lol c230 sport coup

LILBENZ230

Yeah I was being facetious. I am going to make another attempt at getting the VMI.

W203E35

I'm not 100% sure but whenever a car steps foot in a dealer and service is done doesn't it get reported? What i'm trying to say is maybe you can purchase a carfax report and it will tell you step by step details. I purchased a report and it even said when a simple oil change was done.

LILBENZ230

What I am saying is that my Mercedes dealer acknowledges that the car has a service history in their system, but that they cannot give me a print-out of it or even tell me what was done to my car during its first owner's time with it. That just doesn't make sense to me. I have the carfax.

W203E35

We'll that does sound odd, try another dealer. C230 Sport got his maybe you can call the dealer that he called and they can fax you over the information. What does the carfax say does it say anything about what service has been done?