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Ambient Temperature Sensor / Switch HVAC: Testing and Inspection




Step 1:




Step 2:




Step 3:




Step 4:




DIAGNOSTIC PROCEDURE
SYMPTOM: Ambient sensor circuit is open or shorted. 21 or -21 is indicated on auto amp. as a result of conducting Self-diagnosis STEP 2.)

ELECTRICAL COMPONENT INSPECTION




Ambient Sensor
After disconnecting ambient sensor harness connector, measure resistance between terminals 2 and 1 at sensor harness side, using the table.

Part 1 Of 2:




Part 2 Of 2:




If NG, replace Ambient Sensor.