Chevrolet Trailblazer Service Manual page 659

Rear auxiliary HVAC module removal and installation
12. Detach the rear auxiliary HVAC module from the right side and floor of the vehicle.
13. Remove and discard the pass through seal from the rear auxiliary HVAC module.
To Install:
1. Install a new pass through seal onto the rear auxiliary HVAC module.
2. Attach the rear auxiliary HVAC module from the right side and floor of the vehicle.
Torque the bolts to 89 in-lb (10 Nm).
3. Connect the rear auxiliary air outlet ducts to the rear auxiliary HVAC module.
4. Connect the rear auxiliary HVAC module connectors.
5. Install the right rear quarter trim panel.
6. Lift the vehicle.
7. Install the heater hoses onto the rear auxiliary HVAC module under the vehicle.
8. Uncap the a/c refrigerant lines.
9. Install new o-rings onto the a/c line block fittings.