ABS Light after Kingpin Change

Sorry of this is duplicating information elsewhere - couldn't find it!

Helped a mate change his kingpin bearings yesterday. All very easy / straight forward with the exception the ABS sensor screws shearing off on the driver's side, but we were prepared for that so drilled out, refitted everything - no problem. A quick 2 mile test drive at 40-50mph confirmed the wobble had gone and all OK.

This morning on his way to work, when he got to 60mph the ABS light came on and couldn't be made to go off.

We were fairly confident that we hadn't damaged a sensor or wiring, so after much head scratching decided that some muck / rust must have dropped into the teeth on the hub, so decided to strip and clean it this afternoon.

No muck / debris, but we did notice that the gap between the ABS rotor and sensor on the Passenger's side was 1-2mm, whilst the driver's side was at circa 4mm. Decided that must be the cause, so moved it closer to the rotor (2mm gap) and re-assembled everything.

Bingo! ABS light out, tested and working.

Lesson: The sensor re-location is obviously critical if a couple of mm makes the difference between the ABS working or not.

That is correct it is critical. Well done for finding and fixing and the bonus is you have increased your knowledge bank!