1.CHECK BATTERY VOLTAGE OF INTAKE DOOR MOTOR

1. Turn the ignition switch ON.
2. Check voltage between the intake door motor harness connector and ground.

(+) | (−) | Voltage (Approx.)
Intake door motor | —
Connector | Terminal
M254 | 1 | Ground | 12 V

Is the inspection result normal?
YES>>GO TO 2.
NO>>Repair the harnesses or connectors.
2.CHECK INTAKE DOOR MOTOR SIGNAL
Check output waveform between the intake door motor harness connector and ground with the oscilloscope.

(+) | (−) | Output waveform
Intake door motor | —
Connector | Terminal
M254 | 3 | Ground |

Is the inspection result normal?
YES>>GO TO 3.
NO>>Repair the harnesses or connectors.
3.CHECK INTAKE DOOR MOTOR GROUND CIRCUIT

1. Turn the ignition switch OFF.
2. Disconnect the intake door motor connector.
3. Check for continuity between the intake door motor harness connector and ground.

   Intake door motor | — | Continuity
   Connector | Terminal
   M254 | 2 | Ground | Existed

Is the inspection result normal?
YES>>Replace the Intake door motor.
NO>>Repair the harnesses or connectors.