In-Vehicle Sensor Circuit

COMPONENT DESCRIPTION




In-vehicle sensor
The in-vehicle sensor is located on instrument lower panel. It converts variations in temperature of compartment air drawn from the aspirator into a resistance value. It is then input into the auto amplifier.







Aspirator
The aspirator is located on driver's side of heater and cooling unit. It produces vacuum pressure due to air discharged from the heater and cooling unit, continuously taking compartment air in the aspirator.

DIAGNOSTIC PROCEDURE




SYMPTOM: In-vehicle sensor circuit is open or shorted. (22 or -22 is indicated on auto amp. as a result of conducting Self-diagnosis STEP 2.)

Step 1:

Step 2 - 4:

COMPONENT INSPECTION







In-vehicle Sensor
After disconnecting in-vehicle sensor harness connector, measure resistance between terminals 1 and 2 at sensor harness side, using the table.

If NG, replace in-vehicle sensor.