Diagnosis Procedure

AMBIENT SENSOR


Description


COMPONENT DESCRIPTION





- The ambient sensor (1) is installed on the middle of radiator upper support.
- The ambient sensor converts the ambient temperature detected with thermistor into the voltage, and the A/C auto amp. inputs this voltage.

AMBIENT TEMPERATURE CORRECTION
- The A/C auto amp. inputs the temperature detected with the ambient sensor as the ambient temperature.
- Perform the correction of the temperature detected with the ambient sensor for air conditioner control and for ambient temperature display.
- Since the engine heat influences on the ambient sensor during idling condition, the A/C auto amp. retards the ambient temperature indication of the combination meter to avoid the effect of steep temperature change.
- Select and use the initial value of ambient temperature data depending on the coolant temperature when turning the ignition switch from OFF to ON. Use the detection temperature of the ambient sensor at low coolant temperature [less than approximately 56�C (133�F)]. Use the memory data (before the ignition switch is OFF) when the engine is warming up [approximately 56�C (133�F) or more].
- Do not perform the correction of the ambient temperature when the detection temperature of the ambient temperature is less than approximately -20�C (-4�F).

SET TEMPERATURE CORRECTION
The A/C auto amp. performs the correction to the target temperature set by the temperature control switch so as to match the temperature felt by the passengers depending on the ambient temperature detected with the ambient sensor and controls it so that the interior air temperature is always the most suitable.





AMBIENT SENSOR


Diagnosis Procedure

1.CHECK AMBIENT SENSOR POWER SUPPLY CIRCUIT
1. Turn the ignition switch OFF.
2. Disconnect the ambient sensor connector.
3. Turn the ignition switch ON.
4. Check voltage between ambient sensor harness connector and the ground.





Is the inspection result normal?
YES - GO TO 2.
NO - GO TO 4.
2.CHECK AMBIENT SENSOR GROUND CIRCUIT CONTINUITY
1. Turn the ignition switch OFF.
2. Disconnect the A/C auto amp. connector.
3. Check continuity between ambient sensor harness connector and A/C auto amp harness connector.





Is the inspection result normal?
YES - GO TO 3.
NO - Repair the harnesses or connectors.
3.CHECK AMBIENT SENSOR
Check the ambient sensor components. Component Inspection.
Is the inspection result normal?
YES - INSPECTION END
NO - Replace the ambient sensor.
4.CHECK AMBIENT SENSOR OPEN CIRCUIT
1. Turn the ignition switch OFF.
2. Disconnect the A/C auto amp. connector.
3. Check continuity between ambient sensor harness connector and A/C auto amp. harness connector.





Is the inspection result normal?
YES - GO TO 5.
NO - Repair the harnesses or connectors.
5.CHECK AMBIENT SENSOR SHORT CIRCUIT
Check continuity between ambient sensor harness connector and the ground.





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