LEMON Manuals: Even more car manuals for everyone
Home >> GMC >> 2000 >> C3500 HD 6.5 F, Standard >> Repair and Diagnosis >> Heating, Ventilation & A/C (HVAC) >> HVAC Control Systems >> HVAC System - Manual - Escalade, Pickup, TAHOE & YUKON >> Trouble Shooting >> Air Delivery System Check

Air Delivery System Check

NOTE: If vehicle is equipped with auxiliary A/C system, perform all test steps. If vehicle is equipped with front A/C only, perform steps  1- 3 .
  1. Start engine and bring to operating temperature. Turn blower switch to high position. Rotate temperature knob to full hot (Red) position. Rotate mode control knob through each position. Air temperature should be hot and blower motor should operate at high speed. With mode control in defrost position, air will exit from defrost outlets. In bi-level or blend position, air will exit from defrost and heater (floor) outlets. In heater position, air will exit from heater (floor) outlets. In vent position, air will exit from instrument panel vent (A/C) outlets. If airflow does not change as specified, go to FRONT MODE DOOR ACTUATOR INOPERATIVE .
  2. Rotate temperature knob to full cold (Blue) position. Rotate mode control knob through each position. Air temperature will change from hot to cool. If air temperature does not change as specified, go to FRONT TEMPERATURE ACTUATOR INOPERATIVE .
  3. Depress A/C button to turn A/C on. Rotate temperature knob to maximum cold (Blue) position. Depress A/C button to turn A/C off. Rotate temperature knob to medium (Red/Blue) position. Depress recirculation button to recirculate air within passenger compartment. Airflow changing between fresh and recirculated air will be heard as a loud rushing sound and increase in blower motor output velocity. If no change can be detected, go to FRONT AIR INLET ACTUATOR INOPERATIVE .
  4. Place front auxiliary A/C-heater control assembly blower switch in high position. Front auxiliary A/C-heater control assembly is located overhead, above rear view mirror. Turn mode control knob to lower outlet position and turn temperature control to full cold (Blue) position. Auxiliary blower motor should operate at high speed and cold air should flow from lower outlets of the auxiliary A/C system. If air is not cold, go to AUXILIARY TEMPERATURE ACTUATOR INOPERATIVE . If air does not flow from lower outlets, go to AUXILIARY MODE ACTUATOR INOPERATIVE .
  5. Place front auxiliary A/C-heater control assembly mode control knob to upper outlet position and turn temperature control to full hot (Red) position. Auxiliary blower motor should operate at high speed and hot air should flow from upper outlets of auxiliary A/C system. If air is not hot, go to AUXILIARY TEMPERATURE ACTUATOR INOPERATIVE . If air does not flow from upper outlets, go to AUXILIARY MODE ACTUATOR INOPERATIVE .
  6. Place front auxiliary A/C-heater control assembly in REAR position. Go to rear auxiliary A/C-heater control assembly, located above rear headliner. Turn blower switch to high position, mode control knob to lower outlet position and temperature control to full cold (Blue) position. Auxiliary blower motor should operate at high speed and cold air should flow from lower outlets of auxiliary A/C system. If air is not cold, go to AUXILIARY TEMPERATURE ACTUATOR INOPERATIVE . If air does not flow from lower outlets, go to AUXILIARY MODE ACTUATOR INOPERATIVE .
  7. Place rear auxiliary A/C-heater control assembly mode control knob to upper outlet position and turn temperature control to full hot (Red) position. Auxiliary blower motor should operate at high speed and hot air should flow from upper outlets of auxiliary A/C system. If air is not hot, go to AUXILIARY TEMPERATURE ACTUATOR INOPERATIVE . If air does not flow from upper outlets, go to AUXILIARY MODE ACTUATOR INOPERATIVE .
scientia non olet · About LEMON Manuals