Component Inspection

Component Inspection

1. Check A/C Control Unit
(1) Engine "ON".
(2) Disconnect Humidity Sensor.
(3) Measure voltage value between terminal "1" of A/C control unit and chassis ground.
A. Specification : 5V




(4) Is the measured voltage within specifications?
YES
1) Go to "Check Humidity Sensor" procedure.
NO
1) Substitute with a known-good A/C Control Unit and check for proper operation.
If the problem is corrected, replace A/C Control Unit and then go to "Verification of Vehicle Repair" procedure.
2. Check Humidity Sensor
(1) Engine "ON".
(2) Connect Humidity Sensor.
(3) Measure Frequency between terminal "3" and "2" of Humidity sensor while increasing humidity.
A. Specification : Refer the specifications in fig 5)












(4) Is the measured frequency within specifications in fig 5) ? (tolerance limits ± 5%)
YES
1) Check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and then go to "Verification of Vehicle Repair" procedure.
NO
1) Substitute with a known-good Humidity sensor and check for proper operation.
If the problem is corrected, replace Humidity sensor and then go to "Verification of Vehicle Repair" procedure.