OMG...you guys are kidding me?! There is something wrong with the engine coolant system, not intercooler system. There are no sensors in the intercooler system to warn you of issues. The only electrical stuff in the intercooler system is simply the line running to the Bosch pump used in the system which does nothing but powers it on and off.
Check your engine coolant bottle and make sure before starting the car (and it sitting) you have enough coolant to the point where it says on the front "Cold Fill Level."
My "COOLANT" message comes up to, thats what it is, the engine coolant!
EDIT: Also, the only warniing messages you will see if the intercooler system is if your system rich CEL comes up (AIT2 is too high for what the engine is calibrated for) thus the intercooler system is insufficent = density of air is out of whack and too much gas is in for the mixture. Also, your spark plugs will be fouled and the engine will cut out (like you're hitting the rev limiter) at less than normal rpms, such as 5000rpm.
^~~These are also the symptoms the GM Tech Line has to tell whether or not the intercooler pump is working, regardless of the obvious of whether or not coolant is flowing.
Last edited by vandy0419; 01-30-2007 at 06:29 PM.