Quote Originally Posted by Lextech View Post
With the 0411 swap you can easily add T/H mode. There is no indicator light for T/H mode on the GMT400 truck. You give a single PCM pin a MOMENTARY Ground to engage T/H. If you press the button again or cycle the key, T/H is cancelled.

Jeff
Well its not GMT400 its a GMT600 but I think it should work the same way. Did the indicator light work off serial data or is it a pcm output?