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Inspection Procedure Using OBDII Scan Tool




PROCEDURE USING OBDII SCAN TOOL
1. Check A/C idle-up Vacuum Switching Valve.
- Remove A/C idle-up Vacuum Switching Valve. Disconnect A/C idle-up Vacuum Switching Valve connector.





- Measure resistance between terminals.

Resistance: 22 - 42 ohms at 20°C (68°F)

- Measure resistance between each terminal and the body.

Resistance: 1 M ohms or higher.

- Check operation of A/C idle-up Vacuum Switching Valve when battery positive voltage is applied to the terminals of A/C idle-up Vacuum Switching Valve connector.

Battery positive voltage is applied: the air from pipe E is flowing out through pipe F.
Battery positive voltage is NOT applied: The air from pipe E is NOT flowing out through pipe F.


- If OK proceed to step 2.
- If not OK replace A/C idle-up Vacuum Switching Valve.
2. Check voltage between terminal ACV of Engine Control Module connector and body ground.
- Remove glove compartment.
- Turn Ignition Switch ON.





- Measure voltage between terminal ACV of Engine Control Module connector and body ground.

Voltage: 9 - 14 volts.

- If OK proceed to step 3.
- If not OK check for open and short in harness and connector between EFI Main Relay and Engine Control Module.
3. Check air hose and air pipe.
- If OK check and replace Engine Control Module.
- If not OK repair or replace.