1.CHECK AMBIENT SENSOR POWER SUPPLY CIRCUIT

1. Turn the ignition switch OFF.
2. Disconnect ambient sensor connector.
3. Turn the ignition switch ON.
4. Check voltage between ambient sensor harness connector and ground.

   (+) | (−) | Voltage (Approx.)
   Ambient sensor | —
   Connector | Terminal
   E76 | 1 | Ground | 5 V

Is the inspection result normal?
YES>>GO TO 2.
NO>>GO TO 4.
2.CHECK AMBIENT SENSOR CIRCUIT CONTINUITY

1. Turn the ignition switch OFF.
2. Disconnect the A/C auto amp. connector.
3. Check for continuity between the ambient sensor harness connector and A/C auto amp harness connector.

   Ambient sensor | A/C auto amp. | Continuity
   Connector | Terminal | Connector | Terminal
   E76 | 2 | M66 | 37 | Existed

Is the inspection result normal?
YES>>GO TO 3.
NO>>Repair the harnesses or connectors.
3.CHECK AMBIENT SENSOR
Check the ambient sensor components. Refer to Component Inspection.
Is the inspection result normal?
YES>>Replace the A/C auto amp.
NO>>Replace the ambient sensor.
4.CHECK AMBIENT SENSOR CIRCUIT CONTINUITY

1. Turn the ignition switch OFF.
2. Disconnect the A/C auto amp. connector.
3. Check for continuity between the ambient sensor harness connector and A/C auto amp. harness connector.

   Ambient sensor | A/C auto amp. | Continuity
   Connector | Terminal | Connector | Terminal
   E76 | 1 | M66 | 35 | Existed

4. Check for continuity between ambient sensor harness connector and ground.

   Ambient sensor | — | Continuity
   Connector | Terminal
   E76 | 1 | Ground | Not existed

Is the inspection result normal?
YES>>Replace the A/C auto amp.
NO>>Repair the harnesses or connectors.