ACTUATOR CALIBRATION - ATC SYSTEM
The Actuator Calibration function homes and repositions the air-door actuators, removes accumulated positioning errors, and checks for air-door span faults. Once actuated, the entire process takes approximately 90 seconds. Upon completion, all air-door actuators should return to the position that the system is currently requesting. Running the Actuator Calibration function is the only way to detect air-door travel too large faults and air-door travel too small faults. These faults, if present, will display on the scan tool after running the Actuator Calibration function.
STARTING ACTUATOR CALIBRATION - ATC SYSTEM
Use a scan tool to start the Actuator Calibration function.
ACTUATOR CALIBRATION - MTC SYSTEM
Note. Diagnose and repair Actuator Circuit Test faults (DTC 61, 62, 63, 64, 65, 66, 67, 68, 69, 71, and 72) before diagnosing Overcurrent faults (DTC 41, 42, 43, and 44) and Calibration faults (DTC 18, 21, 22, 23, 24, 25, 45, 46, 47, 48, 51, 52, 53, 54, 55, and 56). Diagnose and repair Overcurrent faults (DTC 41, 42, 43, and 44) before diagnosing Calibration faults (DTC 18, 21, 22, 23, 24, 25, 45, 46, 47, 48, 51, 52, 53, 54, 55, and 56).
The A/C-Heater Control automatically runs the Actuator Calibration function upon ignition on after installing a new A/C-Heater Control. The Actuator Calibration function homes and repositions the air-door actuators, removes accumulated positioning errors, and checks for air-door span faults. Once actuated, the entire process takes approximately 90 seconds. Upon completion, all air-door actuators should return to the position that the system is currently requesting. Running the Actuator Calibration function is the only way to detect air-door travel too large faults, air-door travel too small faults, air-door bound faults, and air-door broken linkage faults. These faults, if present, will display when checking for DTCs in the A/C-heater control.
STARTING ACTUATOR CALIBRATION MANUALLY - MTC SYSTEM
Refer to STARTING THE ACTUATOR CIRCUIT TEST / DOOR CALIBRATION FUNCTION - MTC SYSTEM .
ACTUATOR CIRCUIT TEST / DOOR CALIBRATION FUNCTION - MTC SYSTEM
Note. Diagnose and repair Actuator Circuit Test faults (DTC 61, 62, 63, 64, 65, 66, 67, 68, 69, 71, and 72) before diagnosing Overcurrent faults (DTC 41, 42, 43, and 44) and Calibration faults (DTC 18, 21, 22, 23, 24, 25, 45, 46, 47, 48, 51, 52, 53, 54, 55, and 56). Diagnose and repair Overcurrent faults (DTC 41, 42, 43, and 44) before diagnosing Calibration faults (DTC 18, 21, 22, 23, 24, 25, 45, 46, 47, 48, 51, 52, 53, 54, 55, and 56).
The Actuator Circuit Test / Door Calibration function first tests the air-door electrical circuits for shorts and then it homes and repositions the air-doors to remove accumulated positioning errors and to check for air-door span faults. This test / function supplements the continuous actuator drive system diagnostics and can provide greater detail about shorted air-door electrical circuits by identifying up to three door driver circuits shorted simultaneously. This test will also detect air-door travel too large faults, air-door travel too small faults, air-door bound faults, and air-door broken linkage faults. The Actuator Circuit Test / Door Calibration function must be manually actuated. Faults detected will display when checking for DTCs in the A/C-heater control.
STARTING THE ACTUATOR CIRCUIT TEST / DOOR CALIBRATION FUNCTION - MTC SYSTEM
Note. By running the Actuator Circuit Test / Door Calibration Function, the A/C-Heater Control can identify up to three door driver circuits shorted simultaneously. A DTC 72 will set if more than three door driver circuits are shorted in the same direction (e.g. four door driver circuits all shorted to ground) or if two or more door driver circuits are shorted with at least one door driver circuit shorted to ignition and one door driver circuit shorted to ground. To ensure a proper diagnosis, diagnose and repair Actuator Circuit Test faults in the following order: If present, diagnose and repair DTC 72 first, then DTC 62, then DTC 61, then DTCs 64, 66, 68, or 71, and finally DTCs 63, 65, 67, or 69. In addition, always test the door driver circuits after each repair by clearing DTCs, and then running the Actuator Circuit Test / Door Calibration Function, and then checking for DTCs.
To start the Actuator Circuit Test / Door Calibration function for the MTC system, perform the following
Scheme 5
Note. An active DTC 34 will prevent the control from performing certain diagnostic functions and it will prevent proper EBL mode switch and status indicator function. If this occurs, diagnose and repair DTC 34 before running the Actuator Circuit Test / Door Calibration function. Refer to DIAGNOSTIC CODE INDEX article or appropriate HVAC ELECTRICAL DIAGNOSTICS article for the diagnostic test procedure.
- Turn the ignition to the On position.
- Turn the blower motor control (1) to the Off position.
- Press and hold the EBL mode switch (2) down and then turn the blower motor control on. Continue to hold the EBL mode switch down until the EBL status indicator begins flashing. Then, release the mode switch. While the test / function is running, the EBL status indicator will flash once per second. If the test / function passes, the EBL status indicator will stop flashing. However, if the test / function fails, the A/C and EBL status indicators will flash alternately. Faults detected will display when checking for DTCs in the A/C-heater control.