Those holes on the brake pads

[eaglescout526]

You ever wondered what the holes are for on the inside brake pads?

 

 

 

 

 

 

 

Thats where the sensors goes and clips into for the system sentry. 

[Salvagedcircuit]

Nice 

[pizzaman09]

Out of curiosity, how many pads have the sensors for the sentry system?  Of cars that I've seen brake wear sensors on, BMW tends to put a sensor on one front pad and one rear pad.  On the extreme case I've seen Mercedes put a sensor on all eight pads on an 86 560SL. 

[eaglescout526]

1 hour ago, pizzaman09 said:

Out of curiosity, how many pads have the sensors for the sentry system?  Of cars that I've seen brake wear sensors on, BMW tends to put a sensor on one front pad and one rear pad.  On the extreme case I've seen Mercedes put a sensor on all eight pads on an 86 560SL. 

Damn. That’s extreme. The sentry requires 2. One on the left and one on the right. Can’t be placed in the drums. 
Now I know there’s a set of dodge and Chrysler cars from 84-90 that use the same sensor just with a different plug which is no big deal and is an easy swap.