Hello we have a 2010 GMC Acadia with an a/c problem....after running for about 15 min. we noticed that the scan data was showing 24 degrees evap temp and the a/c would start to cycle..The scan data was showing request denied every time the compressor cycled... we ordered a evap sensor from GM and the temp returned to normal...good for about a month...rechecking a no a/c/no cold air complaint the evap sensor data was at 24 degrees again... we disconnected the evap wiring and the sensor read 49 degrees and the a/c started cooling ....next we reread the diag info for the evap sensor and that told us the control head was bad...replaced the control head and had it reflashed to find the same problem with the evap sensor temp reading 24 or our counts were at 1.. we ohm tested the wires from the sensor to the control head no opens or high resistance ohm tested the sensor itself and it was within the spec for our temp here in mesa az .. We also tried adding a ground to the low reference side of the sensor to see if the temp reading would change but it did not. Has anybody had a problem like this ??? Please let me know Thanks Mick

Michael Marcogliese
Owner/Shop Foreman
The Path Less Traveled Automotive
Apache Junction, Arizona, USA