Quick coupla question on this topic:
How many wear sensors are there on the car? All four wheels? Front only? One each front and rear?
Pre 2001 one on each front wheel.
Post 2001 only 1, drivers side.
Can the sensor(s) be changed without pulling the pads out?
Yes.
How does the sensor logic work? (Are they electrically 'normally open' and go short as the pads wear? Or are they 'normally closed' and go open circuit as the pads wear?)
Normally closed, as the pads wear they cut through the wire loop inside the pad and opens the circuit. 
Aha! So an incorrectly fitted sensor, or a poor connection, will give a spurious 'fail' signal. Ta for that. I've always presumed they worked the other way round - as they wore down (with the pads) an internal wire grounded through the disc and closed the circuit.
Ta for the other answers too.
Gaz
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Topic: Brake pad warning (Read 1799 times)