Buckle belt, turn key to on position without starting,wait untill seat belt light goes off on dash, then unbuckle and rebuckle 3 times ending in the buckled postion within 60 seconds. Then start your truck and you should hear a chime sound confirming it was done. You will still see the seatbelt light on the dash but the chime will be gone.
I have a 2012 that I have tried to disable over and over with no luck. I've tried it buckled then key on then unbuckle/rebuckle three times fast then I've done both start the truck after three buckles and turn the ignition off after three buckles. No luck. Can you not disable a 2012?