2002 Trailblazer is only blowing AC through defrost and floor

[scasaz2008]

my AC is only blowing through the defrost and the floor - HELP!! it's a cool 101 degrees here today!!

we have changed out the battery, the actuator on the passenger AND driver side, as well as pulling the HVAC fuse from the fuse box under the rear seat - non of this has helped!

any suggestions???

[Tech II]

That is usually a default position caused by loss of vacuum...

[scasaz2008]

so then how do we repair that "loss of vac"

[gmtech1]

Originally Posted by scasaz2008

my AC is only blowing through the defrost and the floor - HELP!! it's a cool 101 degrees here today!!

we have changed out the battery, the actuator on the passenger AND driver side, as well as pulling the HVAC fuse from the fuse box under the rear seat - non of this has helped!

any suggestions???

Pretty sure the modes are electronically controlled on this one. Did they work normally before the battery was replaced? If so, you may try disconnecting the battery and holding the positive and negative cable ends together for 30 sec or so. This will deplete all capacitors in the car and reset all modules. Then reconnect the battery and see what happens.

[Tech II]

MY BAD.....GMTech1 is correct....you have electrical actuators, not vacuum.....all actuators have a common fuse, HVAC fuse, #39, 10 amp, located in the rear fuse block...