Brake Pad Wear Sensors
06-05-2015 | 11:28 AM
#1
Thread Starter
Member
Joined: Sep 2006
Posts: 142
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Brake Pad Wear Sensors
How many are there suppose to be?
USA 2007 CLK 63
The service manual is unclear so I went to actually look at the car.
One sensor Passenger Rear Caliper
One sensor Driver Front Caliper
To me, it seems odd there is not a sensor for each caliper.
So, is everything in order and two what is suppose to be correct?
Thank you.
P.S. Both the rotors and calipers are labeled Brembo with AMG noted also.
USA 2007 CLK 63
The service manual is unclear so I went to actually look at the car.
One sensor Passenger Rear Caliper
One sensor Driver Front Caliper
To me, it seems odd there is not a sensor for each caliper.
So, is everything in order and two what is suppose to be correct?
Thank you.
P.S. Both the rotors and calipers are labeled Brembo with AMG noted also.
06-07-2015 | 01:15 AM
#2
MBWorld Fanatic!
Joined: Apr 2005
Posts: 3,784
Likes: 81
From: SCV SoCal
2002 CLK430
I’m halfway across the country and can’t check my WIS, but the MBs at my house have sensors on both sides in the front and a single sensor in the rear. That said, a car really only needs one sensor up front and one in the back. That’s because brakes that are performing normally wear evenly on each axle. IE both sets of front pads (left and right) wear out at about the same time, and the same is true for the rear. If one side of one axle is worn to the point where the backing plate is grinding against the disk, and other side isn’t down to the wear sensor, something is very wrong. That would lead me to believe a piston in the caliper may be sticking.
If you really feel there should be a sensor at each corner, then why not 1 sensor for each pad? Think about it. The inner and the outer pads don’t wear at the same rate. Typically the sensor is in the pad that wears fastest (hottest side of the disk), but if you want to really keep track, why not check both inner and outer pad? That’s 8 sensors . . . . . . and have you seen the price on sensors?
Why is it a 2002 CLK brake pad sensor is ninety-four cents, while later ones, like a 2007 CLK sensor, are ten dollars? Basically, it’s a wire wrapped in plastic. When the pads wear to the point where the plastic cover on the sensor grinds off, the wire grounds against the disk, and the pickup triggers a light. Why are there two wires on the later ones (there are 2 wires on a CLS550, can’t say for sure on a CLK550) and how did they get to be 10X the price?
If you really feel there should be a sensor at each corner, then why not 1 sensor for each pad? Think about it. The inner and the outer pads don’t wear at the same rate. Typically the sensor is in the pad that wears fastest (hottest side of the disk), but if you want to really keep track, why not check both inner and outer pad? That’s 8 sensors . . . . . . and have you seen the price on sensors?
Why is it a 2002 CLK brake pad sensor is ninety-four cents, while later ones, like a 2007 CLK sensor, are ten dollars? Basically, it’s a wire wrapped in plastic. When the pads wear to the point where the plastic cover on the sensor grinds off, the wire grounds against the disk, and the pickup triggers a light. Why are there two wires on the later ones (there are 2 wires on a CLS550, can’t say for sure on a CLK550) and how did they get to be 10X the price?
