Tony Berry

2003 C230K Coupe. I had a local brake shop (who I trust more than the $$M-B$$ shop) install new front and rear brake pads. After about a week, the Info Center displayed "Brake Wear, Visit Shop". It went away after the car sat all night, but it came back a couple days later and now it displays constantly. I refuse to pay the dealer to fix something I really don't even want. What is the easiest way to just disable the sensor(s)? Clip a wire? Something in the user accessible menu system?

I attempted to do a forum search, but the search dialog box would just load constantly, never returned anything.

Thanks!

e1000

i think you have to install a new sensor

XenonBenz

x 2

It sounds like your local brake shop didn't install the new brake wear sensor correctly. Go back there and have them check it out.

yeuchau

like everyone else said, you need new sensor
and also from what i know, if the brake wear shows up, than it's bad, you'll need to get new one.

Blake P

As much as I hate to say it, this shop you trust so much should have known to install a new sensor.

BlackLiquorish8

my car is a 2003 also this is kinda a dumb question but if my brakes are goin bad the car will tell me??? i might still change the pads soon b/c the braking sucks and i hate the brake dust

BabyBenz6spd

Like many already have said, the shop you trust should have installed a new sensor.

I got my sensor replaced when I was replacing my rotors and pads. All you need is 1 sensor for the passenger front side. The sensor is like $15 at MOST from the dealer, get it replaced!

03see2thirtyk

A bit curious, how much did it cost/save you to go have your brakes done at this shop that you trust?

Moviela

The brake wear sensor is actually just a little loop of wire that looks like a short circuit to the warning circuit. It is sitting in a hole drilled in the pad near the backing plate. When the pad is about worn out, the sensor is exposed to the brake disc. The wire is worn through, and creates an open circuit. On a C class there are from 1 to 4 sensors, depending on year and brake package. If you unplug the sensor, or cut the wire, it will think that the wire loop has worn through, and alert you with a warning message.

The sensors are a five buck item, and can be installed with your fingers once the wheel is off. There is a connector near the caliper for the sensor. Pay attention to how the cable is laid, it is important to put it back in the way you find it. Cell phone cameras are wonderful to document how it goes before you remove it.

In your situation, it sounds like the sensor connector was not well mated, or not replaced properly. It is also possible that the connector on the car need to be cleaned with alcohol or perchloroethylene. Many brake cleaner sprays are perchloroethylene. It might not be the fault of the brake shop at all, sometimes new parts just fail. It does get a bit toasty where the sensor lives, especially if the shop bedded the pads properly. The high heat might have been too much for a new sensor.

It is a nice safety feature, might as well have it working.

hawaiian

I don't know if anyone's mentioned this yet but sounds like they didn't install a new sensor......

patrick_y

Yes, the car should tell you if the front brakes need new sensors. The rears won't though. It is a message that comes up on the computer display screen in the instrument cluster that will say brake pads need to be replaced.

This is assuming that your car has had the brake sensors properly installed.

It's in the owner's manual...

Tony Berry

Thanks to Moviela for the only answer to my question. I'll take care of this myself.

The rest of you obviously don't remember my MANY threads about how poor my local dealership is. They would have had the same problem and charged me 2-3 times to fix it... blaming a separate issue each time. No thanks.

XenonBenz

Hmm... 5 people replied to your post before Moviela and said you are missing the sensor. Yes, he gave more detail, but still the same answer. You are the one who said you went to a "local reputable brake shop".

Thanks for slapping the 5 of us in the face who took the time to answer your question.

I'll be sure to ignore your posts from now on.

Tony Berry

No need to get offended XB. Moviela was the only one to give the location of the sensor and how it works (closed loop vs. open loop)... the two things I needed to fix the problem. The other posts were of no help unless I wanted to waste time and money at the dealer.

Just to clarify once again, the local dealer has a bad case of "billing fever". They charge you for EVERYTHING and then some. They charged me a full hour of service to change one setting on my car (took 5 minutes from the time I pulled up until the tech was done), then said I was lucky they didn't charge me the minimum of 2 hours. This is the same dealer that charges retail pricing + xx% for all parts. The same dealer that refuses to order by part number, only by VIN, even for parts I KNOW will work (I saw proof here at MBW) and even if I sign a "no return" waiver to remove their liability. It goes on and on. Everyone here keeps harping on the "reputable brake shop"... they are. They are very honest, they do a good job, and they don't overcharge. Just because they aren't fully versed in intricacies of all models of cars is no reason to assume they are incompetent, especially when the dealer has proved time and again to be.

So the 5 faces don't feel slapped... thanks to EVERYONE who responded. Thanks for the response. Thanks again to Moviela for the solution. A response does not constitute a solution, especially when it is "have the dealer replace the sensor".

JimB

BlackLiquorish8

thanx!

XenonBenz

Okay, I get your point. You wanted a DIY answer, even though that's not what you asked for. None of the 5 responses said to "have the dealer replace the sensor". It was "replace the sensor" and I actually said for you to go back to your local brake shop to have them install/fix the sensor.

No biggie, however the way you thanked Moviela made it feel like you were slapping the 5 responders. You said "thanks to Moviela for the only answer to my question", which sounded like you wanted the rest of us to feel like we wasted your time reading our responses.

Rick

Of course....if you had SEARCHED THE FREAKIN' FORUM.....(lol)
you might have found several answers, a dozen DIY's and a few good tips on how to easily do this.

Saprissa

hooray for brake-wear sensors !!

ok.... time to merge with all the other brake-wear sensor threads.....

mleskovar

C32/AMG? Any specific years? Just curious.

trisonics

I had my front brakes done two weeks back at a small repair shop and the brake warning malfunction didn't go away. Turns out they have put in the wrong sensor. They put correct part yesterday and the message is gone.
The part as Moviela said doesn't cost more than 10 bucks and very easy to install.

1. Remove the right side wheel (on 2002 C230 Coupe, not sure abt others) and turn it completely to the left to expose the brake pads.

2. Remove the clamp to expose the inside brakpad. You will see a small hole in it and a sensor that is connected to a wire hanging from above.

3. Buy a new sensor and put it in

03see2thirtyk

Even more curious now if the reputable mechanic:

a) replaced sensor but did not mount/install correctly
b) mounted same sensor after replacing pads
c) did not even bother replacing sensor
d) none of the above

Please keep us updated Tony

Tony Berry

You're a step ahead of me... I spent a few minutes digging into my car this weekend and found the following:

I did, in fact, locate the brake wear sensor, exactly where it was supposed to be. I pulled it out and it looked fine (and quite new). I ohmed across the sensor leads and it was shorted. So I traced the wire back and just before going through the fender wall, I found a heavily rubbed spot where the wire was worn in two. Looks like maybe a grommet or clamp was missing. I fixed the wire (cut and re-spliced) and the problem went away. My cost: about 30 minutes from driving the car into the garage until I drove it out. Had I taken it to the dealer: 2 hour minimum shop labor at $70/hour plus they always seem to find a "bad" part to replace along the way... ~$200.

I figured it wasn't something related to replacing the pads, as the sensor was cutting in and out for several days/week before I had the pads replaced. My general assumption was that once that sensor was broken, it stayed broken.

Thanks for the all the suggestions.