2009 w900 cruise not working

I can't figure out why my cruise isn't working. I get a service light on dash that comes and goes.
My cat et is giving me code.
600-9 cruise control coast (decelerate) switch:abnormal update rate
602-9 cruise control accelerate switch:abnormal update rate

I can watch the screen with cat et and it shows the switch toggling on and off and it shows when I set the cruise but it doesn't set.

I've changed both switches but still nothing. Jakes work fine. It also will not let the engine idle up with the accel-decel switch. I've tried searching these codes for some one with same issues but nothing.

Truck has c15 engine.

 

I'm reading them through cat ET on my laptop through my data port.
2009 W900L last 6 of vin 257405
Engine C15 year model 2008 SER. NO. SDP14398

 

Thanks for reply but have already checked both of those.

 

I tried a working clutch switch from one of my other trucks with no change. What is CECU?

 

I did swap out the switches.
When I pull up the screen on cat et to watch switch activation it shows the cruise will toggle on and off and it also shows the cruise set but it doesn't show it activate.

I have a couple cab controllers out of t660's wonder if there interchangeable?

I was kind of leaning towards cab controller but was hoping it wasn't it since its telling ecm what to do but it's not happening.