Idle Speed Control (ISC) System (Sidekick)
- Warm engine to normal operating temperature. With engine idling, turn on headlights. Note if idle speed increases when headlights are turned on. If idle speed did not increase, proceed to step 2). If idle speed increased, ISC solenoid and wiring circuit are okay.
- Turn engine off. Disconnect ECM connector. The ECM is located at upper left corner of instrument panel. Turn ignition on. Note if battery voltage is present at terminal A3 (Brown/Yellow wire) of ECM connector with headlights on. No voltage should be present with headlights off.
- If no voltage is present with headlights on, check for open in Brown/Yellow wire. See WIRING DIAGRAMS article. If battery voltage was present, using ohmmeter, check resistance between ECM terminals B6 (Light Green/Black wire) and B15 (Blue wire) of ECM connector.
- If resistance is 6.6 ohms, go to step 6). If resistance is not 6.6 ohms, disconnect ISC solenoid electrical connector. Measure resistance between ISC solenoid terminals. Resistance should be 5.4-6.6 ohms.
- Replace ISC solenoid if resistance is not correct. If resistance was correct, check wiring between ECM and ISC solenoid for opens, shorted Blue wire to Light Green/Black wire, or poor connection at ISC solenoid.
- Check ISC solenoid operation. See IDLE SPEED CONTROL (ISC) SOLENOID under IDLE CONTROL SYSTEM in this article. Replace ISC solenoid if defective. If ISC solenoid was okay, check for defective connections at ECM. If connections are okay, substitute ECM and recheck operation.