I have a 2001 2500HD and the Tow Hall wouldn't come on and after several tries it did but again after restarting the truck it will not go on. Any ideas or help?

 

The truck is designed to cancel tow/haul once it has been shut off to prevent the trans from being in tow/haul during normal driving conditions . I would check all fuses & wiring connections to trans also check the tow/haul switch operation. I am sure fuses are fine since it does work. Also pull the trans & transfer case codes with a scanner this could help you diagnose & repair the condition if any codes are stored. These truck did have faulty park neutral switches which is located at the left side of trans.

 

the wiring for the switch is broken. remove the steering column upper and lower covers. follow the orange wiring loom from the t/haul switch to where it secured in the column by a plastic plug. typically, they break where it is secured at the plug. you can either fix the wiring or replace the shift lever.

 

What tech said, he hit the nail on the head