Note. The Smart Junction Box (SJB) is also known as the Generic Electronic Module (GEM).
The interior lighting system consists of the following components
- Door ajar switches (part of the latch assembly)
- Instrument panel dimmer switch
- Interior/map lamps
- Footwell lamps
- Glove compartment lamp
- Luggage compartment lamps
- Luggage compartment ajar switch (part of the latch assembly)
- Remote Function Actuator (RFA) module
- Puddle lamps
- Scuff plate lamps
- SJB
- Vanity mirror lamps
- Ambient lighting switch
- Interior Lighting Control Module (ILCM)
The interior lighting system can consist of 3 subsystems
- Courtesy lamps
- Demand lamps
- Ambient lighting (if equipped)
Principles of Operation
Note. The Smart Junction Box (SJB) is also known as the Generic Electronic Module (GEM).
The SJB supplies voltage to the interior lighting system. The interior lighting system illuminates the courtesy lamps to enhance visibility of the interior while a vehicle door is ajar, and the vehicle speed is less than 15 km/h (9 mph) or 5 km/h (3 mph) for puddle lamps. The SJB controls all interior lighting functions and timing by monitoring inputs from the door ajar switches, the instrument panel dimmer switch and the vehicle speed.
Normal Operation
The Smart Junction Box (SJB) (vehicles without Intelligent Access (IA)) or the Remote Function Actuator (RFA) module (vehicles with IA ) send a voltage signal to each door ajar switch, which is routed to ground when the door is closed (the door ajar switch is closed when the door is closed). When the door is opened, the signal to ground is interrupted, indicating an open door to the SJB or the RFA module.
For vehicles with IA , the RFA module then sends a door ajar message to the SJB over the communication network.
When the SJB detects an open door, the SJB provides voltage to the courtesy lamps.
This pinpoint test is intended to diagnose the following
- Wiring, terminals or connectors
- Door ajar switch
- SJB
- RFA module
The Smart Junction Box (SJB) turns the courtesy lamps on and off by monitoring the dimmer switch input and the dome lamp request input circuits. When the instrument panel dimmer switch is pushed to the second detent up, the backlighting dim up circuit and the dome request circuit are both requested to indicate a request to turn the courtesy lamps on. When the instrument panel dimmer switch is pushed to the second detent down, the backlighting dim down circuit and the dome request circuit are both requested to indicate a request to turn the courtesy lamps off.
This pinpoint test is intended to diagnose the following
- Wiring, terminals or connectors
- Instrument panel dimmer switch
- SJB
The Smart Junction Box (SJB) fuse 9 (15A) supplies power for the interior courtesy lamps. When the SJB receives the required input (such as an open door or request from the instrument panel dimmer switch), the SJB provides voltage to the interior courtesy lamps.
| DTC Description | Fault Trigger Conditions |
|---|---|
| B106E - Solid State Driver Disabled Due to Short Circuit | A continuous DTC that sets when the SJB has temporarily shut down the output driver. The module has temporarily disabled the interior courtesy lamp output because an excessive current draw exists (such as a short to ground). The SJB cannot enable the interior courtesy lamp output until the cause of the short is corrected, the DTCs have been cleared and a successful self-test is run . |
| B106F - Module Disabled Due to External Fault | A continuous DTC that sets when the SJB has permanently shut down the output driver. The module has permanently disabled the interior courtesy lamp output because an excessive current draw fault (such as a short to ground) has exceeded the limits that the SJB can withstand. The cause of the excessive current draw MUST be corrected before a new SJB is installed . |
| B2A35 - Interior Lighting Output Circuit Open | An on-demand DTC that sets when the SJB detects an open from the courtesy lighting output circuit. |
| B2A36 - Interior Lighting Output Circuit Short to Ground | A continuous and on-demand DTC that sets when the SJB detects a short to ground from the courtesy lighting output circuit. |
DTC DESCRIPTION
This pinpoint test is intended to diagnose the following
- Fuse
- Wiring, terminals or connectors
- Scuff plate lamp
- Interior lamp
- SJB
The Smart Junction Box (SJB) provides voltage to the puddle lamps when the courtesy lamps are on (such as when a door is open or when requested from the instrument panel dimmer switch). The puddle lamps have separate ground circuits.
- DTC B2A39 (Puddle Lamp Output Circuit Open) - an on-demand DTC that sets when the SJB detects an open from the puddle lamp output circuit.
- DTC B2A3A (Puddle Lamp Output Circuit Short to Ground) - a continuous and on-demand DTC that sets when the SJB detects a short to ground from the puddle lamp output circuit. This DTC also sets as a result when the SJB fuse 10 (15A) has failed or is removed.
This pinpoint test is intended to diagnose the following
- Fuse
- Wiring, terminals or connectors
- Exterior mirror
- Puddle lamp
- SJB
The Smart Junction Box (SJB) (vehicles without Intelligent Access (IA)) or the Remote Function Actuator (RFA) module (vehicles with IA ) send a voltage signal to each door ajar switch, which is routed to ground when the door is closed (the door ajar switch is closed when the door is closed). When the door is opened, the signal to ground is interrupted indicating an open door to the SJB or the RFA module.
When the SJB or the RFA module detect voltage is provided to the courtesy lamps.
When the Smart Junction Box (SJB) detects a request for the courtesy lamps (such as open door or from the instrument panel dimmer switch), the SJB supplies voltage to the interior courtesy lamps.
DTC B2A35 (Interior Lighting Output Circuit Open) - an on-demand DTC that sets when the SJB detects a short to voltage from the courtesy lamp output circuit.
This pinpoint test is intended to diagnose the following
- Wiring, terminals or connectors
- SJB
- When the Smart Junction Box (SJB) detects a request for the courtesy lamps (such as open door or from the instrument panel dimmer switch), the SJB provides voltage to the puddle lamps.
- DTC B2A39 (Puddle Lamp Output Circuit Open) - an on-demand DTC that sets when the SJB detects a short to voltage from the puddle lamp output circuit.
This pinpoint test is intended to diagnose the following
- Wiring, terminals or connectors
- SJB
The Smart Junction Box (SJB) supplies voltage to the luggage compartment lamp when the battery saver relay is energized. The luggage compartment lamp ground is a series circuit that is comprised of 2 circuits and the luggage compartment ajar switch. When the luggage compartment lid is ajar, the ajar switch closes and completes the ground path by connecting the circuit. The battery saver function provides automatic shutoff of the interior lamps (courtesy lamps and demand lamps) after 10 minutes have elapsed in order to save battery power.
- DTC B1331 (Decklid Ajar Rear Door Circuit Failure) - an on-demand DTC that sets when the SJB detects an open from the luggage compartment ajar input circuit to the SJB .
- DTC B1178:13 (Boot/Trunk Ajar Switch: Circuit Open) - an on-demand DTC that sets when the Remote Function Actuator (RFA) module detects an open from the luggage compartment ajar input circuit to the RFA module.
This pinpoint test is intended to diagnose the following
- Wiring, terminals or connectors
- Luggage compartment lamp
- Luggage compartment lid latch
- SJB
- RFA module
The Smart Junction Box (SJB) energizes the battery saver relay based on inputs from the ignition status, ajar switches, Remote Keyless Entry (RKE) transmitter, keyless entry keypad, and the instrument panel dimmer switch. When the battery saver relay is energized, it supplies voltage to the demand lamps. The demand lamps are grounded at each lamp by the switch.
This pinpoint test is intended to diagnose the following
- Fuse
- Wiring, terminals or connectors
- SJB
The Smart Junction Box (SJB) supplies voltage to the demand lamps when the battery saver relay is energized. The demand lamps are grounded at each lamp by the switch.
This pinpoint test is intended to diagnose the following
- Wiring, terminals or connectors
- Interior lamp
The Smart Junction Box (SJB) provides a battery saver function. The battery saver function provides automatic shutoff of the interior lamps (courtesy lamps and demand lamps) after 10 minutes have elapsed in order to save battery power.
A timer in the SJB is started when the ignition is turned OFF, and all the doors and the luggage compartment lid are closed. When the time-out period for the lamps has elapsed, the voltage is automatically shut off to the lamps by the SJB .
This pinpoint test is intended to diagnose the following
- Wiring, terminals or connectors
- SJB
The Interior Lighting Control Module (ILCM) supplies voltage and ground to the LEDs located in the floor console cup holders, storage tray, storage bin and the front and rear footwells. The ILCM turns the ambient lighting on to a pre-set color and brightness setting when a door is open or the illuminated entry feature is active. The ambient lighting is also active when the ignition switch is in the RUN position and the parking lamps are on.
The ambient lighting select switch is used to cycle through the 7 color combinations or to turn the ambient lighting feature off. There are 4 different color (red, blue, green and white) LEDs housed within each LED assembly.
The ILCM sends a voltage signal to the ambient lighting switch. When the ambient lighting switch (a momentary contact switch) is pressed to cycle the color setting, the voltage signal is routed to ground, indicating a request for the module to cycle the ambient lighting to the next color setting or to turn the ambient lighting off.
The color and brightness settings can only be changed when the ignition switch is in the RUN position, the parking lamps are on and all the doors are closed.
- DTC B2B18 (Ambient Light Switch Input Fault) - a continuous and on-demand DTC that sets when the ILCM detects a short to ground from the ambient lighting select input circuits.
This pinpoint test is intended to diagnose the following
- Wiring, terminals or connectors
- Ambient lighting harness
- Ambient lighting switch
- ILCM
The Interior Lighting Control Module (ILCM) supplies voltage and ground to the LEDs located in the floor console cup holders, storage tray, storage bin and the front and rear footwells. The ambient lighting switch is used to cycle through the 7 color combinations or to turn the ambient lighting feature off. There are 4 different color (red, blue, green and white) LEDs housed within each LED assembly.
The ILCM sends a voltage signal to the ambient lighting switch. When the ambient lighting switch (a momentary contact switch) is pressed to cycle the color setting, the voltage signal is routed to ground, indicating a request for the module to cycle the ambient lighting to the next color setting or to turn the ambient lighting off.
The color and brightness settings can only be changed when the ignition switch is in the RUN position, the parking lamps are on and the doors are closed.
| DTC Description | Fault Trigger Conditions |
|---|---|
| B2B00 - Ambient Light Zone 1 Red Circuit Open | A continuous and on-demand DTC that sets when the ILCM detects an open from the ambient lighting zone 1 red circuit. |
| B2B01 - Ambient Light Zone 1 Red Circuit Short to Ground | A continuous and on-demand DTC that sets when the ILCM detects a short to ground from the ambient lighting zone 1 red circuit. |
| B2B02 - Ambient Light Zone 1 Green Circuit Open | A continuous and on-demand DTC that sets when the ILCM detects an open from the ambient lighting zone 1 green circuit. |
| B2B03 - Ambient Light Zone 1 Green Circuit Short to Ground | A continuous and on-demand DTC that sets when the ILCM detects a short to ground from the ambient lighting zone 1 green circuit. |
| B2B04 - Ambient Light Zone 1 Blue Circuit Open | A continuous and on-demand DTC that sets when the ILCM detects an open from the ambient lighting zone 1 blue circuit. |
| B2B05 - Ambient Light Zone 1 Blue Circuit Short to Ground | A continuous and on-demand DTC that sets when the ILCM detects a short to ground from the ambient lighting zone 1 blue circuit. |
| B2B06 - Ambient Light Zone 1 Signature Circuit Open | A continuous and on-demand DTC that sets when the ILCM detects an open from the ambient lighting zone 1 white circuit. |
| B2B07 - Ambient Light Zone 1 Signature Circuit Short to Ground | A continuous and on-demand DTC that sets when the ILCM detects a short to ground from the ambient lighting zone 1 white circuit. |
| B2B08 - Ambient Light Zone 2 Red Circuit Open | A continuous and on-demand DTC that sets when the ILCM detects an open from the ambient lighting zone 2 red circuit. |
| B2B09 - Ambient Light Zone 2 Red Circuit Short to Ground | A continuous and on-demand DTC that sets when the ILCM detects a short to ground from the ambient lighting zone 2 red circuit. |
| B2B0A - Ambient Light Zone 2 Green Circuit Open | A continuous and on-demand DTC that sets when the ILCM detects an open from the ambient lighting zone 2 green circuit. |
| B2B0B - Ambient Light Zone 2 Green Circuit Short to Ground | A continuous and on-demand DTC that sets when the ILCM detects a short to ground from the ambient lighting zone 2 green circuit. |
| B2B0C - Ambient Light Zone 2 Blue Circuit Open | A continuous and on-demand DTC that sets when the ILCM detects an open from the ambient lighting zone 2 blue circuit. |
| B2B0D - Ambient Light Zone 2 Blue Circuit Short to Ground | A continuous and on-demand DTC that sets when the ILCM detects a short to ground from the ambient lighting zone 2 blue circuit. |
| B2B0E - Ambient Light Zone 2 Signature Circuit Open | A continuous and on-demand DTC that sets when the ILCM detects an open from the ambient lighting zone 2 white circuit. |
| B2B0F - Ambient Light Zone 2 Signature Circuit Short to Ground | A continuous and on-demand DTC that sets when the ILCM detects a short to ground from the ambient lighting zone 2 white circuit. |
DTC DESCRIPTION
This pinpoint test is intended to diagnose the following
- Wiring, terminals or connectors
- Ambient lighting harness
- ILCM
The Interior Lighting Control Module (ILCM) sends a reference signal to the ambient light switch to monitor for a request to change the brightness level. When the switch for the brightness level is pressed, the signal is routed to ground indicating a request to change the brightness level to the next setting.
This pinpoint test is intended to diagnose the following
- Wiring, terminals or connectors
- Ambient lighting harness
- Ambient lighting switch
- ILCM
- DTC U0140 (Lost Communication With Body Control Module ( GEM ) - sets in the Interior Lighting Control Module (ILCM) if data messages are missing or not received from the Smart Junction Box (SJB) over the Medium Speed Controller Area Network (MS-CAN). For a complete list of all network messages, refer to «MODULE COMMUNICATIONS NETWORK»(ref-376006) .
This pinpoint test is intended to diagnose the following
- Wiring, terminals or connectors
- SJB