2018 cascadia Jake don’t work

Selector button lights up when the steering wheel button is pressed, but there’s no Jake and no dash light…
Shop said they looked, I’m not so sure.
I do know I’m cooking brakes quick.
What should i look at?

 

Auto.
Cruise works normal
On this one, right side bottom right button engages Jake. Dash button selects high/med/low.
When toggling the wheel button, the selector lights up, but no indicator on dash and it’s not functioning.

 

Tried that, no go.

 

I believe so. It’s the only malfunction with anything on the dash and smart wheel controls.
Strange thing is, the indicators are active, and except the idiot light and actual Jake brake not functioning, you’d think it should work.
I politely informed dispatch that, unless that was fixed, i won’t be running that truck again.
It’s specific to one load we run and, it’s just not safe to run through the hills of Kentucky and East Tennessee. That Jake is pretty important.