Hey gents. D5 with 58k miles and original brakes.

Just replaced pads and rotors on the rear with a new sensor on passenger side. The brake pad warning light did not shut off.

Im kinda dumfounded. Faulty new sensor? The fronts look like they have alot of life on the outside but hard to tell on the inside. Both front and rear pads and sensors worn down at the same time?

 

Possible it's the front brakes triggering it this time. But - more likely either the new sensor wasn't plugged into the connector fully, or it got broken in installation. If it wasn't seated properly it could have got mashed by the brakes...

Did you do it yourself? If so would pop off the rear wheel with the sensor and check the cable, routing etc. there's not much to it - it's just a wire loop such that the pins are shorted across in normal use and when the tip wears down it brakes the circuit and triggers a warning

You can also test the sensor very easily with a continuity tester on an ammeter if you have one. Should register as basically straight circuit with little resistance.

 

Yes. Just double checked my install and all connections are perfect. Installed a ton of these and never had an issue.

 

Nearly impossible for this to happen actually. The sensor clips onto the rear side of the new pad.

 

And resistance of the wire loop checks out?

There really isn't anything to these - it's a v simple setup. You can double check by shorting across the connector terminals going to the car to confirm the warning goes out. Sounds most likely that the wire itself was faulty or got damaged along the way

Otherwise possible the fronts are now triggering it? I can't remember on this car if it tells you whether it's front or rear (I always thought it odd that most don't tell you..)

 

Vehicle does not differentiate between front and rear.

 

I pulled the sensor out again and jumped the connection. Brake pad warning still didn't go away. Thinking it's gotta be the front sensor at this point. I can see the interior pad on the fronts that well due to the big Brembo calipers so Im thinking they might be worn down to the sensor.

 

I ended up pulling out the front sensor and jumping it and it was the fronts as well. Both the brakes wore down at the same time. 58k miles is not bad I guess.