Principles of Operation

PRINCIPLES OF OPERATION

Smart Junction Box (SJB)
The SJB receives inputs from the following:
- Door ajar switches
- Headlamp switch
- Remote keyless entry (RKE) transmitter/keyless entry keypad switches
- Powertrain control module (PCM) (vehicle speed signal)
- Ignition switch

The SJB uses these inputs to control the output to the battery saver relay, interior lamp relay and the approach lamp relay. Both relays are integral to the SJB and cannot be accessed directly.

Interior Lighting Systems
The SJB grounds the battery saver relay and interior lamp relay coils when any door ajar switch or the headlamp switch is closed. The interior lamp relay then supplies power to the interior lamp circuit. Vehicle speed must be less than 5 km/h (3 mph) for the SJB to ground the interior lamp relay. The interior lamps will remain illuminated for a period of up to 25 seconds after all doors are closed, the ignition is switched from the OFF position, or the SJB receives a vehicle speed signal. Actuating the interior lights from the headlamp switch will operate at any time.

Illuminated Entry
Illuminated entry is activated when a keyless entry keypad switch provides ground on the SJB input or when the SJB receives an unlock signal from the RKE transmitter. The SJB then provides ground to the battery saver and interior lamp relay coils. Illuminated entry is deactivated when the SJB receives a lock signal from an RKE transmitter or if the SJB receives ground inputs from the keyless entry keypad switch lock code. Illuminated entry will also be deactivated when the SJB receives input voltage from the ignition switch.

Battery Saver
The battery saver is activated when the SJB is not receiving voltage input from the ignition switch (OFF position). The SJB will then provide ground to the battery saver relay coil for a maximum of 30 minutes depending on the state of the interior lamp switch inputs to the SJB. The energized battery saver relay switches voltage to the demand lamp circuit and the interior lamp relay coil. After time-out, the SJB removes ground to the battery saver relay disabling the demand lamp circuit.

Approach Lamps
The SJB grounds the battery saver relay and interior lamp relay coils when any door ajar switch or the headlamp switch is closed. The interior lamp relay then supplies power to the approach lamps located on the side view mirrors. The approach lamps will remain illuminated for a period of up to 25 seconds after all doors are closed, the ignition is switched from the OFF position, or the SJB receives a vehicle speed signal.