The automatic transmission shift lock control is a safety device that
prevents an inadvertent shift out of PARK when the ignition is ON. 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 automatic transmission shift lock control switch |
• | The park/neutral position switch |
With the ignition in the ON position, battery positive voltage is supplied
to the park/neutral position switch. When the transmission is in the PARK
position the contacts in the park/neutral position switch are closed.
This allows current to flow through the switch to the automatic transmission
shift lock control switch. The circuit continues through the normally-closed
switch to the automatic transmission shift lock control solenoid.
The automatic transmission shift lock control solenoid is permanently
grounded. This energizes the automatic transmission shift lock control
solenoid, mechanically locking the shift lever in the PARK position.
When the driver presses the brake pedal the contacts in the automatic
transmission shift lock control switch open, de-energizing the automatic
transmission shift lock control solenoid. This allows the shift lever
to move from the PARK position.