CM570 high idle enable

[Johnny LongRifle]

Hey guys,

Working on my brothers 2000 W900b with a CM570. I installed a new (rebuilt) ECM a few months ago after the truck had been down for 9 months or so. Got it running and back on the road. That apparently ticked off the mechanic who had been "working" on it. Long story short, that guy broke into it one night and changed a bunch of parameters making the truck almost unuseable. He turned on a idle shutdown timer, installed a speed limiter, turned off the manual cooling fan function, and disabled cruise control.

I borrowed a scan tool from my Cornwell dealer and got 3 of the 4 functions working again.What I cant figure out is how to enable the cruise control and high idle functions. I've enabled every cruise control and PTO option I can find, to no avail. The ECM is not seeing the cruise switch functions. I have tested the circuits between the switches and the ECM and all is well. Even tried grounding the circuits at the ECM to see if the state changes, and they do not.

What am I missing here? Im an auto mechanic and don't really have a lot of experience with big trucks, but I can read a schematic and look at data on the scan tool, so Im not a total newb. Any help is appreciated.