Did some searching here and other places but could not find an answer.

My wear sensor warning (amber) came on but the next day the alarm was no longer on.

I would have thought the warning would have stayed on.

I know it is suppose to come on when it reaches the the last 25% or so.

Is this typical or should I suspect something else.

Physically look at the pads and the rears or both worn more than the fronts but still has some pads left (ie 25% range or so). Right at 35K miles so that wear make sense.

I have all parts (front and rear) including new sensors ready to replace but just want to make sure something else isn't up.

Also plan to flush brake fluid since it is coming up on 2 years since the last flush.

I will be able to check new vs worn sensors.

Thanks for any feedback.

 

If you are at the hysteresis point for the switches they won't make reliably. Once worn past that point they will. Make sense?

 

Thanks, Got that, sort of almost there but not totally there.

 

My '07 XK wore through its rear pad to metal at 35K miles - with no sensor warnings whatsoever. I usually get 75K+ miles on rear pads. Mfgs used to mount a metal tab on brake pads that would scrape against the rotor when the pads were worn - the noise of the scraping was your "sensor warning." My point is not to rely totally on a brake sensor for pad life - do a visual check.
I did get a sensor warning respecting an ABS failure, which turned out to be a failed "speed sensor."

 

My 07 pad sensors were simplistic by design. A metal contact encased in a plastic housing. Drivers front, and Passenger rear only.
When the pads and plastic encasement wore to the point the metal contact touches the rotor, it completes a ground for the circuit and triggers a low pad warning.

Typically you will have plenty of pad surface left (designed safety margin) to get you by as you order parts or arrange for service.