Automatic Transmission Shift Lock Control Circuit Description

Description
The auto trans shift lock control system is comprised of the following components:
^ The stoplamp/auto trans shift lock control switch near the base of the steering column used to de-energize the auto trans shift lock control actuator.
^ The auto trans shift lock control actuator mounted within the floor console, that is serviced with the park/lock cable.

Operation
The auto trans shift lock control system is a safety circuit that prevents the vehicle from accidently shifting out of PARK when the ignition is ON. The console is equipped with a auto trans shift lock actuator. This actuator, when energized, physically holds the gear shift lever from moving out of PARK when the ignition is ON. The actuator de-energizes, allowing the gear shifter to move, by pressing the brake pedal.

Circuit Description
When the ignition switch is turned to ON, ignition positive voltage is supplied from the ignition switch to the park relay coil in the rear fuse block. Battery positive voltage is supplied at all times to the park relay switch. The powertrain control module (PCM) monitors the park/neutral position switch to determine the position of the gear shifter. When the gear shifter is in PARK, the PCM sends a Class 2 message to the RIM. The RIM energizes the park relay by grounding the control circuit of the park relay. With the park relay energized, battery positive voltage is provided from the NSBU fuse in the rear fuse block through the contacts of the park relay and the normally-closed stoplamp/auto trans shift lock control switch to the auto trans shift lock control actuator. The auto trans shift lock control actuator, which is always grounded, then energizes, holding the gear shifter in the PARK position. Depressing the brake pedal opens the contacts of the stoplamp/auto trans shift lock control switch, removing power from the auto trans shift lock control actuator. The actuator de-energizes. allowing the driver to move the gear shifter out of PARK.
When the gear shifter moves out of PARK, the PCM sends a Class 2 message to the RIM. The RIM de-energizes the park relay which disables the auto trans shift interlock actuator. Once the vehicle is out of PARK, the auto trans shift interlock actuator remains de-energized when the brake pedal is released and the stoplamp/auto trans shift lock control switch contacts return to the normally-closed state.

Reverse Lockout System Description
The reverse lockout system is comprised of the following components:
^ The reverse lockout actuator mounted within the floor console, that is serviced with the floor console.
^ The Dash Integration Module (DIM), which controls the reverse lockout actuator.

Reverse Lockout System Operation
The reverse lockout system prevents the console gear shifter from being accidentally bump into REVERSE, while the vehicle is moving over 5 mph for 15 seconds or longer with the ignition ON.

Reverse Lockout System Circuit Description
With the ignition in the ON position, battery positive voltage is supplied the HVAC fuse to the battery positive voltage circuit of the reverse lockout actuator. When the dash integration module (DIM) determines that the ignition is in the ON position and vehicle speed is greater than 5 mph for 15 seconds. The DIM grounds the control circuit of the reverse lockout actuator. When energized, a mechanical pin on the reverse lockout actuator is moved to the outward position. The pin provides a physical stop on the console shifter, preventing movement of the shifter into REVERSE or PARK.