HU11 - Check Idle

- Key Off.

- Transmission in Park (wheels blocked and parking brake engaged).

- A/C, heater and all accessories are off.

- key on, engine running.

- Engine at normal operating temperature and cooling fan off.

WARNING: DO NOT UNPLUG COOLING FAN. IT MAY CAUSE ENGINE OVERHEATING.

- Connect Scan Tool.

- Access engine RPM PID.

NOTE: Engine idle RPM is controlled by the PCM and can not be adjusted. The PCM is calibrated to control idle at the speeds listed below. When performing this test, verify the RPM is within the specification. If the engine is allowed to idle for an extended period of time, or if the engine temperature is hot enough to require cooling fan operation, It may be necessary to turn the Engine Off and repeat this test procedure.

Idle speed: 768 ±25 RPM.

- Access IAC PID, idle air percent duty cycle.

- Is the IAC PID reading 20% to 45% duty cycle?

YES -- GO to HU12. HU12 - Check Idle Control Pressure

NO -- GO to HU13. HU13 - Check IAC Solenoid For Proper Function