What about intercepting the wire that is toggled from the BCM to the PCM or whichever one it was? From reading the post I got the impression that final wire to the PCM is on when the tow/haul light is on, and off when the light is off, not only when the button is depressed.

There are some other things that go on with the tranny in tow/haul mode that aren't able to be changed in EDIT that I could find. The lack of engine braking is the biggest thing I noticed, but I think there are some other things to that too.

 

I'll post a few pictures of the pages with the tow/haul info. I don't know if I interpreted the diagram right now that I look at it again. Might be a little while though before I post them.

I haven't messed around with my Edit stuff much here lately but, you're right if the tow/haul mode engages some engine braking features. Any good pages on what exactly the tow/haul mode does?

 

I think that's the thing ... you don't have engine braking when tow/haul is activated unless the selector is in the gear the tranny is in, i.e. The tranny is in 3, but the selector is in D, the engine will fall to an idle and not do any braking, where is if you move it to 3 it will activate the engine braking.

I wish GM would publish white papers on stuff like that. It would make all this customizing **** a lot easier.

 

That'd be cool.

 

my plan with the tow haul button would just be for momentary nitrous blasts, as long as i hold it it would spray.

i plan on haveing a 3 pos nitrous on switch. pos one would be off, pos 2 would be on but only with the tow haul button and it would also use the saftey devices like the WOT swich and the window switch. pos 3 would be automatic or no tow haul button, anytime it is floored it will be spraying. probably just put a little 50shot in there an who knows, i may not even need it.