[garagerog]

You'll have to check with your dealer to see if programming is available to allow that function for extended idle. I peruse the GM truck forums from time to time and on at least the newer ones GM will not allow the dealer to bypass idle time unless the p/u is used for law enforcement, game dept. etc.

 

[garagerog]

The Blazer is not a vehicle that you would typically find at a construction site where there indeed may be a reason for extended idle. This and the fact that the OP hasn't been back to respond leads me to believe that the OP has a nefarious reason for wanting to do this, to be able to use the HVAC system while leaving a child, elderly/disabled person, or pet unattended.