A/C Idle-Up Valve Circuit
NOTE:
The A/C idle-up valve may also be referred to as A/C idle-up Vacuum Switching Valve (VSV).
- The Engine Control Module (ECM) controls the A/C idle-up valve for maintaining proper idle speed when A/C is turned on. Check A/C idle-up valve operation. See A/C IDLE-UP VALVE (VACUUM SWITCHING VALVE - VSV) under IDLE CONTROL SYSTEM. Replace A/C idle-up valve if defective. If the A/C idle-up valve operates correctly, access the ECM. The ECM is located below driver's side seat leg, near emergency brake lever.
- Turn ignition on. Using voltmeter, check voltage between terminal No. 21 (Red/Blue wire) on ECM and chassis ground. See Fig 1.
- Voltage should be 9-14 volts. If voltage is within specification, go to next step. If voltage is not within specification, check for defective EFI main relay or wiring harness between EFI main relay and ECM. See EFI MAIN RELAY under RELAYS. See appropriate wiring diagram in WIRING DIAGRAMS article.
- Check for defective air hose and pipe at the A/C idle-up valve. The A/C idle-up valve is located on side of air cleaner case, near the air intake, and contains a Black 2-pin electrical connector. See Fig 2.
- If air hose or pipe are defective, replace components as necessary. If air hose and pipe are okay, check ECM ground circuit. If ECM ground circuit is okay, substitute another ECM and recheck system operation.