Principles of Operation

Principles of Operation

NOTE: The smart junction box (SJB) is also identified as the generic electronic module (GEM).

Ignition Switch
The ignition switch is controlled by the ignition lock cylinder with a key. When the ignition lock cylinder is turned using the key, a mechanical connection positions the ignition switch to the selected position and allows the ignition switch to send voltage to specific components.

Multi-function Switch
The multi-function switch (high beam/low beam, flash-to-pass, turn signal and windshield wiper) controls the various components electrically. The headlamp switch sends constant voltage to the headlamps when placed in the ON position, while the flash-to-pass is a momentary switch used to send voltage to the headlamp high beams only. The headlamp high beam/low beam switch sends voltage to the low or high beam headlamps while the headlamps are on. The turn signal switch portion of the multi-function switch operates the left and right turn signals. The windshield wiper switch function uses a ground signal to activate the various wiper modes and the wiper/washer.

Key Release Interlock Actuator
On vehicles equipped with a floor-mounted transmission selector lever, the key release interlock actuator (also known as the key removal inhibit solenoid) is an electronically controlled solenoid that prevents the ignition key from being removed from the ignition cylinder unless the transmission selector lever is in the PARK position. The actuator is mounted to the steering column directly behind the ignition cylinder.

When the transmission selector lever is placed in a position other than PARK, the park detection switch opens and the key release interlock engages. This prevents the ignition key from being removed from the ignition cylinder.

When the transmission selector lever is placed in the PARK position, the park detection switch closes and the key release interlock disengages, allowing the ignition key to be removed from the ignition cylinder.

On vehicles equipped with a column-mounted transmission selector lever, the key release interlock actuator is a mechanically controlled device that prevents the ignition key from being removed from the ignition cylinder unless the transmission selector lever is in the PARK position.

When the transmission selector lever is placed in a position other than PARK, the shift assembly cable moves to block the ignition key from being removed from the ignition cylinder.

When the transmission selector lever is placed in the PARK position, the shift assembly cable moves to allow the ignition key to be removed from the ignition cylinder.