jhartmac

I know the front brakes have the electronic sensor but does the back disc brakes have them also?

stevenle21

yep

yeuchau

all i know is that 2002 has one in front and one in the rear

mleskovar

My '01 320 has one on the passenger rear, none on the driver rear. Once, when rotating tires, I checked the rear pads and the inside rear driver's side pad had less than .01" remaining and the pad on the other rear wheel with the sensor had .02" left before it even hit the plastic on the sensor. Needless to say, I don't trust the sensors.

yeuchau

yah
that happens
should have sensor on all 4 and obc should tell us which is the one that needs to be changed.

SUNILP

w203 cars DO NOT have sensors on all the wheels. Just one in front and one in rear. my w124 has a sensor on each pad! Total of 8 sensors.

Racin_fool

some of the earlier W203 cars didn't have a sensor in the rear. Most people are surprised by this, but I would suggest taking a look at your brakes once in a while.

pnoye2

What shock me the most is that the Mrs car only had 1 (one) brake sensor ...on the F/R, I thought I'd share

jhartmac

I just changed my front pads with ceramic, and both sides had the electronic sensors..........needless to say I still have the message coming up about brake wear visit workshop etc etc lol, so not sure if I have to "clear" the error- (not sure how) or probably just change the rear pads.

mleskovar

What kind of ceramic pads did you put on? Dust? Cost? The low pad warning goes away on its own after you replace the offending sensor. Sounds like you have low pads in the rear!

jhartmac

Raybestos friction master ceramic $56.00 for the front, havent priced the back yet.

faz

Hi,

I don't get a chance to visit or contribute much to this site, but I certainly appreciate feedback from all here. Anyhow, this is something that I can share with you all, and for future visitors/searchers:

I just did the rear brake pads for my 2002 C240, and even though the dealer checked (so she said) and sold me 1 sensor in addition to pads, after completing the brake pad job, I still had the sensor in my hand, and will be returning it (if they get it back) tomorrow. My C240 does NOT have a rear brake pad sensor.

Thought I would share this with everyone here.

cheers,
faz

yeuchau

i think you also have to changed sensor
when that sensor wear shows up on the obc, then you will need new sensor as well, cause old one will be wear out as well.

badger

The W203 Rear Brake sensor is on a case by case basis. If you purchase your sensors from the dealership, ask them. They are the best resource for this.

My 2003 C240 has only a front passenger brake sensor.

btw...since we're talking about this, it is advisable to spray the sensor socket with an MAF (Mass Air Flow) sensor cleaner or other electronic safe cleaner. I've had the sensor warning fail to shut off on my twice now. Its a pain to take it all back apart again.

jhartmac

I thought the same thing about the sensors, they may be "touching" and causing an error that is the two wires I mean, or just need to be replaced and of course cleaned too, I ll do that next nice day out, havent had many here lately.

badger

The message clears when new sensors have been replaced. If you replace the pads early enough, you may be able to reuse your old sensor. The wear on it is obvious. There is a really small rod that sticks down into the pad (less than 1/8 in wide) and as the sides of it wear, the sensor activates. Nothing electronic that you need to do though to get rid of it other than swapping it.