Diagnostic Routine K

Diagnostic Routine K

Diagnostic Overview

Incorrect or Erratic Direction of Airflow From Outlets

Refer to Wiring Diagram Set 55 for schematic and connector information Electrical Diagrams.

Normal Operation and Fault Conditions

During an actuator calibration cycle, the HVAC (Heating, Ventilation, and Air Conditioning) module drives the defrost mode door or the panel/floor mode door until the door reaches the internal stops in the HVAC (Heating, Ventilation, and Air Conditioning) case. If either mode door is temporarily obstructed or binding during a calibration cycle, the HVAC (Heating, Ventilation, and Air Conditioning) module may interpret this as the actual end of travel for the door. When this condition occurs and the HVAC (Heating, Ventilation, and Air Conditioning) module commands the actuator to its end of travel, the airflow may not be from the expected outlets.

DTC Fault Trigger Conditions






Pinpoint Test

1. CHECK THE DEFROST MODE DOOR OR PANEL/FLOOR MODE DOOR ACTUATOR CIRCUITS FOR AN OPEN

1. Ignition OFF.

2. Disconnect: HVAC (Heating, Ventilation, and Air Conditioning) Module C228A.

3. Disconnect: Defrost Mode Door Actuator or Panel/Floor Mode Door Actuator.

4. For the defrost mode door, measure:





5. For the panel/floor mode door, measure:





Are the resistances less than 3 ohms?






2. CHECK THE DEFROST MODE DOOR OR PANEL/FLOOR MODE DOOR ACTUATOR CIRCUITS FOR A SHORT TO GROUND

1. For the defrost mode door, measure:





2. For the panel/floor mode door, measure:





Are the resistances greater than 10,000 ohms?






3. CHECK THE DEFROST MODE DOOR OR PANEL/FLOOR MODE DOOR ACTUATOR CIRCUITS FOR A SHORT TO POWER

1. Ignition ON.

2. For the defrost mode door, measure:





3. For the panel/floor mode door, measure:





Is there any voltage present?






4. CHECK FOR CORRECT HVAC (Heating, Ventilation, and Air Conditioning) MODULE OPERATION

1. Ignition OFF.

2. Disconnect and inspect all the HVAC (Heating, Ventilation, and Air Conditioning) module connectors.

3. Repair:

- corrosion (install new connector or terminals- clean module pins)
- damaged or bent pins- install new terminals/pins
- pushed-out pins- install new pins as necessary

4. Reconnect the HVAC (Heating, Ventilation, and Air Conditioning) module connectors. Make sure they seat and latch correctly.

5. Operate the system and determine if the concern is still present.

Is the concern still present?