What the graph shows is my ABS does not show a rear sensor reading until almost 10mph. At 7mhp or so it starts to show a flaky reading. Then at 10 mph it comes in steady and is consistent with the front two. The problem is when I am slowing down and the rear sensor input drops out at around 10mph the ABS system thinks the rears are locked up and you get the pulsing in the the brake pedal.

Now here's the thing. I very very recently rebuilt my rear axle assembly including changing the rear ABS sensor for a new one. I know the pickup ring is good and installed properly. And also I have had this problem for a long time. It is identical before and after the rear axle rebuild. For 4-5 years I have just used the truck with the ABS 60a fuse pulled with no problems. But I want to fix this sucker.

So assuming, as I am doing, that the pick up ring and sensor are good... What can cause this low speed lack of signal? Corroded connections between the sensor and ABS module?
Thanks

 

ABS module, or poor connection in the harness.

 

X2 with carcrazy assuming your work is correct and sensor is good that's the only other options

 

anyone got a module they're desperate to get rid of? lol

 

This is what I am reading for my problem.
Any clue what "sensor output out of sync" means?



ABS Misfire, ABS Too Sensitive, ABS Fires On Normal Stop
Possible source of problem may be:

Damaged rear sensor ring. Remove rear sensor from differential and inspect sensor ring.

Damaged front sensor ring. Inspect both front sensor rings for damaged or missing teeth.

Sensor output out of sync. If left front sensor output is out of sync, go to TEST E . If right front sensor
output is out of sync, go to TEST G . If rear sensor output is out of sync, go to TEST J .

Sensor circuit. Go to INTERMITTENT FAILURES to test sensor circuits.

Wire insulation. Inspect wiring harness from front sensor knuckle to frame for worn of chafed wire
insulation.

Rear brake adjustment, brake linings. Eliminate base brake system as cause of problem.

Loose sensors. Tighten sensors.

 

Even though my problem is almost always rear sensor or pickup ring I have fixed it by replacing the ABS module. It was not an intermittent problem. It was constant. I drove the truck and had the problem. Them immediately changed the ABS module and now it is fixed. Graph after new module.
You can see the rear now reads at the lower speeds.
Thanks for all comments.