Unusual dash vent problem

[Chevrolet1698]

Sunday I replaced the blower motor resistor in my '04 Silverado 4x4 and now it blows air and heat only through the top dash vents under the windshield. No matter what allowing mode it gets put in, nothing blows through the front dash vents. Do I have a bad damper door? If so, how do I get at it?

[Arth]

You may but first try the "reset" procedure. If you have auto ac you unplug it and plug it back in. Start the truck and let it run for a few. Defaults to 64 I think and it cycles all the modes.

[tramz]

If your still having issues after the "reset" procedure, it possible your door mode actuator needs replacing. It's above the accelerator pedal.

[txab]

A re-calibration may fix you up. Try disconnecting the battery for
a few minutes. Reconnect it. Or remove the HVAC/ECAS fuse for a minimum of 10 seconds.

Re-install the HVAC/ECAS fuse.

 

Then turn the key to the on position, but
don't start. Don't touch the HVAC controls. Let them do whatever that
want to do. Air flow may change outlet points during this time. Wait
about 1 minute. Turn key off.Remove it. Opening and closing the door can
make a difference as the vehicle controls see this as "cycle"
completion. Insert key and start the vehicle and drive it a short distance and see
how it performs. You may indeed need to replace an actuator.