Vehicles equipped with the Fast Idle System have a FAST
IDLE switch and a FAST IDLE lamp mounted on the instrument panel. The Fast
Idle System is used in order to increase the engine idle to a preset speed
while the vehicle is stationary. The fast idle speed values are programmed
in to the PCM using a scan tool. The Fast Idle System is used for the following
conditions:
| • | During cold weather in order to decrease the time needed for the
engine to reach normal operating temperature. |
| • | During hot weather in order to increase the A/C compressor speed
and improve efficiency of the A/C system. |
| • | Aid in maintaining proper charge of the vehicle batteries during
the high current draw caused by the blower motors used during the operation
of the heaters or A/C system. |
Conditions for Engaging the Fast Idle System
When all of the following conditions are present the idle speed will
increase to the selected value and the FAST IDLE lamp will illuminate.
| • | The transmission is in Park (P) or Neutral (N) |
| • | Vehicle speed is not detected |
| • | The FAST IDLE switch is depressed and released |
Conditions for Disengaging the Fast Idle System
When any of the following conditions are present the engine speed will
return to the normal engine idle speed and the FAST IDLE lamp will turn OFF:
| • | The engine is not running |
| • | The transmission is not in Park (P) or Neutral (N) |
| • | Vehicle speed is detected |
| • | The FAST IDLE switch is depressed |
