The automatic transmission shift lock control system is a safety device that
prevents an inadvertent shift out of PARK when the engine is running. The driver must
press the brake pedal before moving the shift lever out of the PARK position. The
system consists of the following components:
• | The automatic transmission shift lock control solenoid |
• | The body control module (BCM) |
• | The powertrain control module (PCM) |
The BCM controls the voltage to the shift lock control solenoid through the
shift lock control solenoid controlled voltage circuit. The following conditions must
be met before the BCM will supply voltage to the shift lock control solenoid:
• | The ignition is in the ON position. |
• | The PCM sends an input to the BCM indicating the transmission is in the
PARK position. |
• | The BCM determines the brake pedal is not applied according to the brake
pedal position. |
Since the shift lock control solenoid is permanently grounded, the BCM supplies
voltage to the automatic transmission shift lock control solenoid, mechanically locking
the shift lever in the PARK position as the solenoid energizes. When the brake pedal
is applied, the BCM turns the control voltage output of the shift lock control solenoid
OFF, de-energizing the shift lock control solenoid. The de-energized solenoid releases
the mechanical lock allowing the driver to move the shift lever out of the PARK position.
When the transmission is out of the PARK position, the shift lock control solenoid
remains de-energized.
During remote start operation the BCM will energize the shift lock control circuit,
locking the shift lever in the PARK position.