OK, I have replaced the 4 bumper sensors, the control module and the dash switch. That damn yellow OFF lite just keeps looking back at me. I have a wiring diagram and, according to it, I have replaced all of the major components. And I have verified the backup lites come on when I shift in to reverse.

Looking for any suggestions on what I should do next.

DSMMH

 

Go to the dealer????

The dealer will hook up to their computer and your truck will tell them which sensor or part is malfunctioning.

I had a sensor go bad 2 years ago and they just hooked it up, ordered the one sensor that was bad and it was fixed the next day.

Yes... I know you don't want to spend all that money at the dealer, but you may have paid to replace sensors or parts that were not actually broken.

Good luck,