Red light of inter axel differentel switch means what?

I have no idea what that light signifies maybe a self-destruct sequence or something. I'd get it checked out

 

Don't know what that light is for but it's not the IAD.

When the diff lock is engaged a red light should come on right by the word 'lock'.

 

Call your company, talk to the maintenance department. They would be most likely to know.

 

It means the mother ship is trying to call you back home ... mother is very concerned that you have not come home for dinner the last three nights ... you must be wasting away with no good home cooking ... if the light stays on for a steady 12 hours ... you and the truck will be beemed up to mother for your required meals ...

Seriously ... I'd just put a piece of black electrical tape over it, if everything is working/driving properly ...

 

The 2017 Cascade manual Chapter 16.1, Drive Axles/Differential Locks says the red light indicates the DCDL (Driver Controlled Differential Lock) is engaged. It also mentions that if you can't disengage it by normal means, to see the FL service center.

 

Oops, Cascadia. Sorry