If I fit front pads will warning light go off??

Manofkent

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Planning to fit new pads this weekend - will the warning light go off after new ones are fitted - if not how best to get it done? I will try to be careful not to damage sensor (Also working on park brake this w/e!)
Thanks
C
 

amb67

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If the warning lamp is on you will need a new sensor, they wear away, that's how they are activated.

The sensors are quite cheap from Ebay or even your local Mercedes dealer.
 

mersum1es

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As above, new sensors!
 

grober

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Usually the insulation on the sensor wires goes brittle with the heat off the brakes and flakes off, allowing the wire to "earth" Since earthing through the disc is how they work anyway this has the same effect as the pad being worn through and the light comes on. As above^^^ the solution is to renew the sensors each time with the pads.
 

amb67

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The sensors don't earth through the discs, the sensors are a part of an electrical circuit and operate by breaking or completing that circuit. The brake pads wear down and expose the wiring that completes the circuit, once the circuit is broken the warning lamp is illuminated.

Hope this helps
 

television

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The sensors don't earth through the discs, the sensors are a part of an electrical circuit and operate by breaking or completing that circuit. The brake pads wear down and expose the wiring that completes the circuit, once the circuit is broken the warning lamp is illuminated.

Hope this helps
There are actually two systems in use, the early till about 2001 ish used a sensor pin that put the warning lamp on if the pedal was pressed, as the sensor pin made an ground contact via the disc.

Yes later system use the closed/open circuit method where a wire is cut and the warning comes on.

All systems are self resetting once the pads and sensors replaced.

Certainly the twin wire later systems do not lend themselves to re using the sensors as they are made from carbon type material.
 

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