Heater & Air Conditioning Control System (DTC/Circuit Diagnosis)

1. Turn ignition switch OFF.
2. Disconnect in-vehicle sensor connector.
3. Turn ignition switch ON.
4. Check voltage between in-vehicle sensor harness connector and ground.

   +		-		Voltage (Approx.)
   In-vehicle sensor
   Connector	Terminal
   M25	1	Ground		5 V

Is the inspection result normal?

YES

GO TO 2.

NO

GO TO 4.

1. Turn ignition switch OFF.
2. Check continuity between in-vehicle sensor harness connector and ground.

   In-vehicle sensor		--		Continuity
   Connector	Terminal
   M25	2	Ground		Yes

Is the inspection result normal?

YES

GO TO 3.

NO

Repair harness or connector.

Check in-vehicle sensor. Refer to Component Inspection .

Is the inspection result normal?

YES

Replace front air control. Refer to Removal and Installation - Front Air Control .

NO

Replace in-vehicle sensor. Refer to Removal and Installation .

1. Turn ignition switch OFF.
2. Disconnect front air control connector.
3. Check continuity between in-vehicle sensor harness connector and front air control harness connector.

   In-vehicle sensor		Front air control		Continuity
   Connector	Terminal	Connector	Terminal
   M25	1	M56	36	Yes

Is the inspection result normal?

YES

GO TO 5.

NO

Repair harness or connector.

Check continuity between in-vehicle sensor harness connector and ground.

Is the inspection result normal?

YES

GO TO 6.

NO

Repair harness or connector.

1. Turn ignition switch ON.
2. Check voltage between in-vehicle sensor harness connector and ground.

   +		-		Voltage (Approx.)
   In-vehicle sensor
   Connector	Terminal
   M25	1	Ground		0 V

Is the inspection result normal?

YES

Replace front air control. Refer to Removal and Installation - Front Air Control .

NO

Repair harness or connector.