Ambient Sensor

AMBIENT SENSOR





Description

COMPONENT DESCRIPTION

Ambient Sensor





The ambient sensor (1) is attached on hood lock stay assembly. It detects ambient temperature and converts it into a resistance value which is then input into the unified meter and A/C amp.

AMBIENT TEMPERATURE INPUT PROCESS
The unified meter and A/C amp. equips a processing circuit for the ambient sensor input. However, when the temperature detected by the ambient sensor increases quickly, the processing circuit retards the unified meter and A/C amp. function. It only allows the unified meter and A/C amp. to recognize an ambient temperature increase of 0.33�C (0.6�F) per 100 seconds.
As an example, consider stopping for a few minutes after high speed driving. Although the actual ambient temperature has not changed, the temperature detected by the ambient sensor increases. This is because the heat from the engine compartment can radiate to the front bumper area, location of the ambient sensor.




Component Function Check
1.PERFORM SELF-DIAGNOSIS
Perform self-diagnosis function STEP-2. Diagnosis Description Unified Meter & A/C Amp Without ACCS (WITHOUT ACCS) or Diagnosis Description With ACCS Unified Meter & A/C Amp (WITH ACCS).
21 or -21 is displayed.
YES - Go to Diagnosis Procedure. SEE Diagnosis Procedure.
NO - INSPECTION END




Diagnosis Procedure
1.CHECK VOLTAGE BETWEEN AMBIENT SENSOR AND GROUND
1. Disconnect ambient sensor connector.
2. Turn ignition switch ON.
3. Check voltage between ambient sensor harness connector and ground.





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





Is the inspection result normal?
YES - GO TO 3.
NO - Repair harness or connector.
3.CHECK AMBIENT SENSOR
Check ambient sensor. SEE Component Inspection.
Is the inspection result normal?
YES - Replace unified meter and A/C amp.
NO - Replace ambient sensor.
4.CHECK CIRCUIT CONTINUITY BETWEEN AMBIENT SENSOR AND UNIFIED METER AND A/C AMP.
1. Turn ignition switch OFF.
2. Disconnect unified meter and A/C amp. connector.
3. Check continuity between ambient sensor harness connector and unified meter and A/C amp. harness connector.





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





Is the inspection result normal?
YES - Replace unified meter and A/C amp.
NO - Repair harness or connector.




Component Inspection
1.CHECK AMBIENT SENSOR
1. Turn ignition switch OFF.
2. Disconnect ambient sensor connector. Exploded View.
3. Check resistance between ambient sensor terminals.





Is the inspection result normal?
YES - INSPECTION END
NO - Replace ambient sensor.