New guy question about the mpvi3 device and a slow 3rd gen tahoe.

[STINKIN421]

Sup, new guy here with absolutely no experience in tuning or how to run a tuning program, but im gonna learn! So i have a 09 tahoe slightly modified and it ran great for 6 months after a rebuild and tune but now im having gmlan communication issues, getting u0100, p0700 and p2160. i know what the codes generally mean but my question is with the MPVI3 can i diagnose the problem further without having to rip the whole harness apart and pulling every pin in every connector? thanks for the time and glad to be here.

[gtstorey]

No mpvi won’t help for this. Spend 20 bucks on an ac delco tds subscription to the oem service manual for diagnostic procedures for those codes.

This seems to all tie to the transmission so have you done a visual inspection on that point?

[STINKIN421]

I figured it would be a longshot. I actually found a website that has damn near everything on vehicle's including service bulletins and repair procedures. ive been up and down that harness, in and out every connector having to do with the gmlan, I even replaced the resistor! its just a frustrating situation. Appreciate the info.

[MarcWolfe]

Most times I've seen a loss of coms code, it was just a low battery. See it farely often at work.