Did you find anything out on your dilemma? I am having kinda the same issues, gauges drop to zero while driving, intermittently. Replaced the ignition switch, checked and verified every fuse while setting still and everything working fine. Scanner says no codes. Only seen it error while driving/moving. Above schematic will help, didn't think of HVAC module thrown into the mix.
Saturday, November 24th, 2012 AT 4:37 PM