No sense in starting a new thread - I am running into the same issue as OP. Cruise control comes on. but trying to set a speed isn;t working. Yes I know how to use it - been using it since I bought the truck new.
No codes on the dash, no SES, no brake light, nada. The little "speedo" pic shows up on the DIC when I turn cruise on but nada when trying to set the speed.
I just had the rear diff rebuilt so I was concerned there were sensors on the axels or something that didn't get transferred. over?
If its a brake switch then this is super coincidental that the switch broke while the rear diff was getting rebuilt? Seems odd. That brake switch is under the dash by the bake pedal? Is it at the brake calipers? If someone has apart number, I would def appreciate it. Let me know. Thanks.
hard to say, I believe you will either need a scanner that can read the condition for not engaging the cruise or throw parts at it, the t2's 2021+ are the only ones with electronic brake pad sensors so it's not that. the brake switch can be a issue from what I understand they send out a couple signals one for the lights and one for things like cruise.
it's also "maybe" a possibility that if a abs sensor is off a tiny bit it could be a problem but not enough to throw a code.
in other words I think it's going to be technical, for instance does your have the hud? and all the little nannies? camera on the windshield etc if one of those is out of syn it could be a reason also.
does auto start work?
if you have a scanner available it would be wise to just break it out and start poking around at stuff, like see what the brake pedal reads, I think it has to be at a specific % at rest, etc