62–COMMON DOOR DRIVER CIRCUIT SHORTED TO IGNITION (MTC) (CONTINUED)
For the Manual Temperature Control (MTC) circuit diagram (Refer to 24 - HEATING & AIR CONDITIONING - SCHE-
MATICS AND DIAGRAMS).
For a complete wiring diagram Refer to Section 8W.
Theory of Operation
NOTE: This DTC will display as active if the ignition is not cycled after running the Actuator Circuit Test /
Door Calibration Function. Otherwise, it will display as stored until cleared.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, diag-
nose 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.
•
When Monitored:
When running the Actuator Circuit Test / Door Calibration Function.
•
Set Condition:
If the A/C Heater Control detects a short to voltage on the (C66) Front Mode Door Common Driver circuit /
(C939) Rear Mode Door Common Driver circuit / (C55) Left Blend Door Common Driver circuit / (C68) Recir-
culation Door Common Driver circuit.
Possible Causes
(C66) FRONT MODE DOOR COMMON DRIVER CIRCUIT / (C939) REAR MODE DOOR COMMON DRIVER
CIRCUIT / (C55) LEFT BLEND DOOR COMMON DRIVER CIRCUIT / (C68) RECIRCULATION DOOR COMMON
DRIVER CIRCUIT SHORTED TO VOLTAGE
A/C HEATER CONTROL
Diagnostic Test
1.
CHECK THE (C66) FRONT MODE DOOR COMMON DRIVER CIRCUIT, (C939) REAR MODE DOOR
COMMON DRIVER CIRCUIT, (C55) LEFT BLEND DOOR COMMON DRIVER CIRCUIT, & THE (C68)
RECIRCULATION DOOR COMMON DRIVER CIRCUIT FOR A SHORT TO VOLTAGE
Turn the ignition off.
Disconnect the A/C Heater Control C2 harness connector.
Turn the ignition on.
Measure the voltage of the (C66) Front Mode Door Common Driver
circuit, (C939) Rear Mode Door Common Driver circuit, (C55) Left
Blend Door Common Driver circuit, (C68) Recirculation Door Common
Driver circuit.
Is the voltage above 0.2 volts on any of the circuits?
Yes
>> Repair all circuits with a voltage above 0.2 volts for a short
to voltage.
Perform BODY VERIFICATION TEST – VER 1. (Refer to 8
- ELECTRICAL/ELECTRONIC CONTROL MODULES -
STANDARD PROCEDURE).
No
>> Go To 2
24 - 140
HVAC - ELECTRICAL DIAGNOSTICS
WK