Got an error alerts on dashboard: Stab Sys Service, and Traction Failure Light on. No error code from OBD II scanner, no other error mentioning ABS.
I have been struggling for couple of days and tried many solutions of other threads/posts.
I have checked ABS sensor, Yaw Sensor, Transfer Case Motor Sensor, which usually caused Stab sys service alerts, however, none of them worked!

Eventually, it turns out to be a problem of "Steering Wheel Position Sensor". It just reminds me that i have replaced my steering column shaft a while back, and some steering wheel got spinned and not centered even i installed it back on the new steering column shaft.
I tried to recalibrate and find the center of the steering position sensor. Then, i'm using a multimeter to measure the resistence between the pins of the connector socket.
This might be also a way to diagnostic the position sensor whether it's worn out or not.
1. Pull out the wire assembly connector from the socket of the position sensor. Disassemble column shaft from the main steering wheel, so you can spin the steering wheel as many circles as you can without engaging the wheels.
2. There're 8 PINs in the socket. #2 from the left is Ground, which connects to the black pin.
3. Locate Pin #6 from left.
4. Measure the resistance between #2 and #6 by the multimeter with range of 2k ohm or 20k ohm
5. If you keep spinning the wheel, you will the see the resistance jumping up and down correspondingly from 0.74 to 10.13. Which will give LOW or HIGH signal to BCM, i believe.
6. Since the sensor should measure a range of -720 degree to +720 degree, so i need to find a center of the resistance range, and at that point, the steering wheel should at the right position with all wheels directing forward directly.
7. After span steering wheel every circle at 12 clock, i noted the resistance from the multimeter. I tried anti-clockwise spinning about 6 rounds, and then clockwise with 10 rounds.
8. Eventually, i got a series of resistance notes: Infinite, 0.741, 0.743, 4.68, 10.09, 10.13, Infinite. If you keep spinning anti-clockwise from 0.741, it will be decreasing, and until half round, it will turn to infinite. then jump again back to 10.x. Then, you know that's the top left boundary infinite.
9. So, the center turns out to be with resistance of 4.68, lock the steering wheel.
10. Hook up with the column shaft, and connect the socket.
11. Start the car, the error may still be there. Take a ride with some turns, the error will be gone!

 

damn! the Stab Sys service error has been fixed, however, airbag light is on. i forgot about the clock spring!!! i spinned too many circles on one direction that the clock spring was broken... i should take the position sensor off and do the calibration!