Chart C-9 Fast Idle Solenoid Check: VIN N (5.7L), VIN T (4.3L)

Fig. 070 - WIRING DIAGRAM for Chart C-9 Fast Idle Solenoid Electrical Check. VIN N, VIN T:

CHART C-9

FAST IDLE SOLENOID ELECTRICAL CHECK

4.3L VIN "T"

5.7L VIN "N"

The Fast Idle Solenoid is a ECM controlled plunger type solenoid which is normally retracted (de-energized). It is extended (energized) when engine coolant temperature is below 38°C (68.4°F) (cold engine) or above 120°C (216°F) (overheating engine).

Fig. 069 - Chart C-9 Fast Idle Solenoid Electrical Check.:

1. With engine at "normal" operating temperature Fast Idle Solenoid plunger should be contracted. (de-energized.
2. Disconnecting the coolant temperature sensor simulates a cold engine. Fast Idle Solenoid should extend.(energize).
3. Determines if solenoid mal-function is caused by open solenoid, open circuit or ECM.
4. Solenoid is extended when it should be retracted. This step checks for grounded circuit, grounded solenoid or faulty ECM.