[Leah1]

I'm going to be changing my rear pads soon and the car shows 8000 miles left but they do look pretty low to me.
So the sensor hasn't triggered yet can I still reuse the old sensor wire and have the proper count down as if I biught a new one or does it need to be changed to get it to work as it should ?

[kiel_dafo_kenyg_as]

No proper count down with the old sensor. The sensor is two stage. Once the first stage is worn through you can't reset the computer without showing the red lifting ramp every time you turn ignition on.

If you are skilled and want to save the money for a new sensor just unplug the old sensor, short the two pins in the plug (car side), reset computer and plug the old sensor back again. If this doesn't work the front sensor is partially worn also and you will have to unplug/short it like you did the rear one. Then reset and plug both sensors back.

From now on the count down wouldn't be proper though but it you'll still get a warning light when the pads are worn down to limit.

It's easier to buy a new sensor.

[Leah1]

Yeah I think it's best to buy new