2007 Chevy Trailblazer, 4.2L 2WD, with a very occasional occurrence of the ABS activating and pumping up the pedal under the driver's foot just before it comes to a stop.
Don't know how long it's been since the codes were cleared, but ABS history codes were:
C0455
C0244
U1000
U1016
U1064
No ABS light, only the tire pressure light that, at times, flashes even though all tires are generously aired.
Cleared all the codes and watched the wheel speed sensor data as I drove. Firstly, all WSS feeds except RR never read lower than 2; RR always reads zero, thought that was due to it being solid rear axle and only having one rear WSS which read as LR. As I'm driving nothing acts up, but the RF sensor reads down to 5 - very occasionally 4 - and drops straight to 2. Always does it, during decel and acceleration. Okay, says I, wheel speed sensor is bad and the ABS is kicking in because it thinks that wheel is locking up.
Replace sensor: no change in data, and now the ABS is kicking in on most stops. Saw the RR sensor data jump to a triple digit number for a split second as the ABS pumped up under my foot, then return back to its usual zero. And that's where I'm currently at.
Help?
Don't know how long it's been since the codes were cleared, but ABS history codes were:
C0455
C0244
U1000
U1016
U1064
No ABS light, only the tire pressure light that, at times, flashes even though all tires are generously aired.
Cleared all the codes and watched the wheel speed sensor data as I drove. Firstly, all WSS feeds except RR never read lower than 2; RR always reads zero, thought that was due to it being solid rear axle and only having one rear WSS which read as LR. As I'm driving nothing acts up, but the RF sensor reads down to 5 - very occasionally 4 - and drops straight to 2. Always does it, during decel and acceleration. Okay, says I, wheel speed sensor is bad and the ABS is kicking in because it thinks that wheel is locking up.
Replace sensor: no change in data, and now the ABS is kicking in on most stops. Saw the RR sensor data jump to a triple digit number for a split second as the ABS pumped up under my foot, then return back to its usual zero. And that's where I'm currently at.
Help?