Idle Speed Control (ISC) System
- Warm engine to normal operating temperature. Ensure idle speed is correct. Apply parking brake, block drive wheels and place transaxle in Neutral.
- Install jumper wire between terminals TE1 and E1 of check connector located under left seat. See Figure. Engine RPM should increase to 1000-1200 RPM for 5 seconds and then return to idle.
- If engine RPM was not within specification, check ISC valve, wiring to ECU, and ECU grounds. If engine RPM was within specification, remove jumper wire. Turn ignition off.
- Unplug ISC valve connector on bottom of throttle body. Using ohmmeter, measure resistance between terminals B+ and ISC1, and between ISC2 and B+. See Fig 1. Replace valve if resistance is not within 18.8-22.8 ohms.
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