1.CHECK BATTERY VOLTAGE OF AIR MIX DOOR MOTOR (DRIVER SIDE)

1. Turn the ignition switch ON.
2. Check voltage between the air mix door motor (driver side) harness connector and ground.

(+) | (−) | Voltage (Approx.)
Air mix door motor (driver side) | —
Connector | Terminal
M252 | 1 | Ground | 12 V

Is the inspection result normal?
YES>>GO TO 2.
NO>>Repair the harnesses or connectors.
2.CHECK SIGNAL OF AIR MIX DOOR MOTOR (DRIVER SIDE)
Check output waveform between the air mix door motor (driver side) harness connector and ground with the oscilloscope.

(+) | (−) | Output waveform
Air mix door motor (driver side) | —
Connector | Terminal
M252 | 3 | Ground |

Is the inspection result normal?
YES>>GO TO 3.
NO>>Repair the harnesses or connectors.
3.CHECK GROUND CIRCUIT OF AIR MIX DOOR MOTOR (DRIVER SIDE)

1. Turn the ignition switch OFF.
2. Disconnect the air mix door motor (driver side) connector.
3. Check for continuity between the air mix door motor (driver side) harness connector and ground.

   Air mix door motor (driver side) | — | Continuity
   Connector | Terminal
   M252 | 2 | Ground | Existed

Is the inspection result normal?
YES>>Replace the air mix door motor (driver side).
NO>>Repair the harnesses or connectors.