TROUBLESHOOTING & INSPECTION

Air Control Valve

1. If the car is running, turn OFF engine.
2. Place a mirror at the end of the air cleaner.
3. Inspect the position of the air control valve. The proper position is with the fresh air vent open and the hot air inlet closed.
4. If the position is not as described in Step 3, check the air control valve linkage for sticking.

   Fig. 1: Inspect the position of the air control valve with a mirror

   Fig. 2: Air control valve operating conditions OPERATION OF THE AIR CONTROL VALVE

Vacuum Motor

1. Keep mirror in position and engine OFF.
2. Remove the vacuum hose from the vacuum motor.
3. Connect a separate piece of the same type of hose to the now vacant vacuum motor. Insert the other end of the new hose into your mouth and draw in a breath, creating a vacuum in the vacuum motor.
4. Check the position of the air control valve. The fresh air vent should be closed and the hot air inlet open.
5. Now, pinch the hose attached to the vacuum motor so that the vacuum is not instantly lost. The valve position described in Step 4 should be maintained for more than 30 seconds.

   NOTE: If the conditions described in Steps 4 and 5 are not observed, replace the vacuum motor.

Temperature Sensor

WARNING
Engine must be cold before starting this test.

1. Keep the mirror in position in front of the air horn as shown in Fig. 7.
2. Start the engine and keep it idling.
3. Check the position of the air control valve immediately after starting. The fresh air vent should be closed and the hot air inlet open.
4. Continue to watch the air control valve as the engine warms up. The fresh air vent should gradually open.

   NOTE: If the conditions described in Steps 2 and 3 are not observed, replace the temperature sensor.