From time to time over the last few years (100KLM) the ABS light has come on.
Usually cleared itself after several trip cycles. The last month more frequently.
until it stayed on all the time. All other operation remains normal.
last week removed the wheel speed sensors and cleaned rust which had accumulated from the wheel disk splash guard on the sensor (Magnetic). This restored Abs function after several drive cycles. All well for 3 days. Then triggered again.ThisABS,ETSalways is triggered when reversing the vehicle and in the first few wheel revolutions.
I finally relented and found a mechanic that had a code reader that could interpret the error codes stored in memory. (You get what you pay for in a mechanic, a story for another day)
The code from the X431 Tool Report

C1140 Steering angle sensor (N49)
Steering angle sensor is not initialized
135 Sporadically fault in CAN communication with:Motor electronics
146 Sporadically Rpm n3 too high Externally toothed disc carrier
Where is the Steering angle sensor located? What is a toothed disk carrier?
I have located a sensor on the rack and pinion box. Is the disk carrier the speed wheel sensor?
Any help is appreciated

 

What about the brake light switch? A faulty brake light switch can cause these issues that you are describing. It is inexpensive and relatively easy to change.

 

C1140 Steering angle sensor (N49)
Steering angle sensor is not initialized
135 Sporadically fault in CAN communication with:Motor electronics
146 Sporadically Rpm n3 too high Externally toothed disc carrier
Where is the Steering angle sensor located? What is a toothed disk carrier?

Steering angle sensor requires normalising after the battery has been discionnected. Turn steering wheel from maximum lock one way to maximum lock the other way and back again with the engine running to assist in managing to turn the wheel. Thats all you have to do. This sensor determines when the car is going straight.

135?....Intermittent CAN may be due to disconnection of the brake sensors when you cleaned them and turning on the ignition whilst sensor disconnected.. i.e. the ECU sensed an open circuit.
Alternatively it's possibly water/corrosion on the CAN (low voltage/current sensor signal wiring. Corrosion causes a SIGNIFICANTLY difference in circuit resistance) which is difficult to locate.

146?....best guess....Plausibility issue? RPM of component A and B out of range based on components being linked in some mechanical way.

Dirty wheel speed sensors do give the ABS fault you identify.
Sure the sensor to harness connections are good, clean and fully connected both FRONT and REAR?

Clear faults and see if they reappear at ignition ON or only when you go for a drive.

Stuart

 

Good info. Update to consider.
I checked the only sensorI could locate on the rack and pinion steering box. Disconected cable and attempted to remove sensor. two torx and two allen screws. The two hex would not come out. The risk of damage to the switch persuaded me to stop. ( is this switch under steering fluid preasure?)
After one drive cycle the ABS codes clered themself. The tapping on the sensor or the disconnecting of the connectorfor this sensor appears to have made the error condition disappear. How does this sensor record the the steering angle.

 

So did you also do a lock to lock normalise? If so I suggest this was the reason for the fault clearing itself.

I don't know the exact location of the steering angle sensor...I had always considered it to be on the column but this may be wrong.
There is also a speed sensitive pressure regulating device in the system.

Stuart

 

I know of the lock to lock proceedure. this was used many times but made no difference over the last two weeks.
I drove the car it was raining heavy.I stopped for coffee. after restarting car ABS light was off.
Still off sofar.
I suspect the square sensor is involved which is mounted on the steering box.

 

Still looking for the location of the steering angle sensor.
anyone know where the preasure switch is located in the steering system?