The interior lighting system consists of the following components
- Dome/map lamps
- Luggage compartment lamp
- Luggage compartment lamp
- Ambient lighting LEDs (if equipped)
- Vanity mirror lamps (integrated into the sun visors) (if equipped)
- Pony projection lights
- Instrument panel dimmer switch
- Door ajar switches
- Luggage compartment lid ajar switch
- Glove compartment lamp
- Body Control Module B (BCM-B)
- Smart Junction Box (SJB)
The interior lighting system can consist of up to 3 subsystems
- Courtesy lamps
- Demand lamps
- Ambient lighting (if equipped)
Principles of Operation
The Smart Junction Box (SJB) supplies voltage to the interior lighting system. The interior lighting system illuminates the courtesy lamp to enhance visibility of the interior. When a vehicle door is ajar and the vehicle speed is less than 15 km/h (9 mph), or the instrument panel dimmer switch is in the DOME LAMP position, the SJB provides voltage to the courtesy lamp circuit. The SJB controls all interior lighting functions and timing by monitoring inputs from the door ajar switches, the instrument panel dimmer switch, and vehicle speed.
The instrument panel dimmer switch receives a voltage signal from the SJB. The instrument panel dimmer switch provides variable resistance for backlighting the Instrument Panel Cluster (IPC) and a toggle on/off function for the courtesy lamp.
The Remote Keyless Entry (RKE) receiver is contained inside the SJB. When the SJB receives an unlock request from a RKE transmitter, it unlocks the doors and turns on the courtesy lamp.
Normal Operation
The Smart Junction Box (SJB) sends a voltage signal to the door ajar switches. When the door is closed, the voltage signal is routed to ground. When the door is opened, the signal to ground is interrupted indicating an open door to the SJB.
When any door is opened, or an unlock request from a programmed Remote Keyless Entry (RKE) transmitter is detected, the SJB provides voltage to the courtesy lamp.
This pinpoint test is intended to diagnose the following
- Wiring, terminals or connectors
- Door ajar switch
- SJB
The Smart Junction Box (SJB) monitors the instrument panel dimmer switch status to determine if the courtesy lamp is requested. Based on the instrument panel dimmer switch status, the SJB supplies voltage to the courtesy lamp.
This pinpoint test is intended to diagnose the following
- Wiring, terminals or connectors
- Instrument panel dimmer switch
- SJB
Voltage is supplied to the courtesy lamp by the Smart Junction Box (SJB) fuse 9 (15A). Based on the input status, the SJB supplies voltage to the courtesy lamp.
| 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 courtesy lamp output because an excessive current draw exists (such as a short to ground). The SJB cannot enable the 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 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 FAULT TRIGGER CONDITIONS
This pinpoint test is intended to diagnose the following
- Fuse
- Wiring, terminals or connectors
- Overhead console
- SJB
The Smart Junction Box (SJB) sends a voltage signal to the door ajar switches. When the door is closed, the voltage signal is routed to ground. When the door is opened, the signal to ground is interrupted indicating an open door to the SJB.
The SJB also monitors the instrument panel dimmer switch status to determine if the courtesy lamp is requested. When the instrument panel dimmer switch is rotated to the DOME LAMP position, ground is supplied to DOME LAMP request input circuit.
When the request from the instrument panel dimmer switch is detected, any door is opened, or an unlock request from a programmed Remote Keyless Entry (RKE) transmitter is detected, the SJB supplies voltage to the courtesy lamp.
| DTC Description | Fault Trigger Conditions |
|---|---|
| B1320 - Driver Door Ajar Circuit Open | An on-demand DTC that sets when the SJB detects an open from the LH front door ajar input circuit. |
| B1328 - Passenger Door Ajar Circuit Open | An on-demand DTC that sets when the SJB detects an open from the RH front door ajar input circuit. |
| B1688 - Lamp Dome Input Circuit Short To Ground | An on-demand DTC that sets when the SJB detects a short to ground from the instrument panel dimmer switch circuit. |
| 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. |
DTC FAULT TRIGGER CONDITIONS
This pinpoint test is intended to diagnose the following
- Wiring, terminals or connectors
- Door ajar switch
- Instrument panel dimmer switch
- SJB
The Smart Junction Box (SJB) supplies voltage to the demand lamps using the battery saver relay. The overhead console map lamp shares ground with the courtesy lamp.
This pinpoint test is intended to diagnose the following
- Wiring, terminals or connectors
- Overhead console
- Sun visor (vanity mirror lamp)
- Glove compartment lamp
- SJB
Power is supplied to the luggage compartment lamp from the demand lighting circuit. Ground for the luggage compartment lamp is controlled by the luggage compartment lid latch. When the luggage compartment lid is opened, a switch inside the latch closes and completes the path to ground.
- DTC B1331 (Decklid Ajar Rear Door Circuit Failure) - an on-demand DTC that sets when the Smart Junction Box (SJB) detects an open from the luggage compartment lid ajar input circuit.
This pinpoint test is intended to diagnose the following
- Wiring, terminals or connectors
- Luggage compartment lamp
- Luggage compartment lid latch
- SJB
The Smart Junction Box (SJB) controls the battery saver function. The battery saver function provides automatic shutoff of the interior lamps (courtesy and demand lamps) after 10 minutes have elapsed in order to save battery power.
This pinpoint test is intended to diagnose the following
- Wiring, terminals or connectors
- SJB
The Body Control Module B (BCM-B) supplies voltage and ground to the LEDs located in the floor console cup holders, console storage bin, driver and passenger scuff plates, both door map pockets and the front and rear footwells. The message center is used to cycle through the color combinations or to turn the ambient lighting feature off. There are 3 different color (red, blue and green) LEDs housed within each LED assembly.
The BCM-B has a built-in self-test that cycles through red, green and blue colors for each zone separately. Using this test may help diagnose a single color failure.
| DTC Description | Fault Trigger Conditions |
|---|---|
| B127B:11 - Ambient Lighting Zone 1 Output Red LED: Circuit Short To Ground | A continuous DTC that sets when the BCM-B detects a short to ground from the ambient lighting zone 1 red circuit. |
| B127E:11 - Ambient Lighting Zone 1 Output Green LED: Circuit Short To Battery or Open | A continuous DTC that sets when the BCM-B detects a short to ground from the ambient lighting zone 1 green circuit. |
| B1281:11 - Ambient Lighting Zone 1 Output Blue LED: Circuit Short To Ground | A continuous DTC that sets when the BCM-B detects a short to ground from the ambient lighting zone 1 blue circuit. |
| B127C:11 - Ambient Lighting Zone 2 Output Red LED: Circuit Short To Ground | A continuous DTC that sets when the BCM-B detects a short to ground from the ambient lighting zone 2 red circuit. |
| B127F:11 - Ambient Lighting Zone 2 Output Green LED: Circuit Short To Ground | A continuous DTC that sets when the BCM-B detects a short to ground from the ambient lighting zone 2 green circuit. |
| B1282:11 - Ambient Lighting Zone 2 Output Blue LED: Circuit Short To Ground | A continuous DTC that sets when the BCM-B detects a short to ground from the ambient lighting zone 2 blue circuit. |
| B127D:11 - Ambient Lighting Zone 3 Output Red LED: Circuit Short To Ground | A continuous DTC that sets when the BCM-B detects a short to ground from the ambient lighting zone 3 red circuit. |
| B1280:11 - Ambient Lighting Zone 3 Output Green LED: Circuit Short To Ground | A continuous DTC that sets when the BCM-B detects a short to ground from the ambient lighting zone 3 green circuit. |
| B1283:11 - Ambient Lighting Zone 3 Output Blue LED: Circuit Short To Ground | A continuous DTC that sets when the BCM-B detects a short to ground from the ambient lighting zone 3 blue circuit. |
| B127B:15 - Ambient Lighting Zone 1 Output Red LED: Circuit Short To Battery or Open | A continuous DTC that sets when the BCM-B detects a short to battery or open from the ambient lighting zone 1 red circuit. |
| B127E:15 - Ambient Lighting Zone 1 Output Green LED: Circuit Short To Battery or Open | A continuous DTC that sets when the BCM-B detects a short to battery or open from the ambient lighting zone 1 green circuit. |
| B1281:15 - Ambient Lighting Zone 1 Output Blue LED: Circuit Short To Battery or Open | A continuous DTC that sets when the BCM-B detects a short to battery or open from the ambient lighting zone 1 blue circuit. |
| B127C:15 - Ambient Lighting Zone 2 Output Red LED: Circuit Short To Battery or Open | A continuous DTC that sets when the BCM-B detects a short to battery or open from the ambient lighting zone 2 red circuit. |
| B127F:15 - Ambient Lighting Zone 2 Output Green LED: Circuit Short To Battery or Open | A continuous DTC that sets when the BCM-B detects a short to battery or open from the ambient lighting zone 2 green circuit. |
| B1282:11 - Ambient Lighting Zone 2 Output Blue LED: Circuit Short To Ground | A continuous DTC that sets when the BCM-B detects a short to battery or open from the ambient lighting zone 2 blue circuit. |
| B127D:15 - Ambient Lighting Zone 3 Output Red LED: Circuit Short To Battery or Open | A continuous DTC that sets when the BCM-B detects a short to battery or open from the ambient lighting zone 3 red circuit. |
| B127F:15 - Ambient Lighting Zone 3 Output Green LED: Circuit Short To Battery or Open | A continuous DTC that sets when the BCM-B detects a short to battery or open from the ambient lighting zone 3 green circuit. |
| B1283:15 - Ambient Lighting Zone 3 Output Blue LED: Circuit Short To Battery or Open | A continuous DTC that sets when the BCM-B detects a short to battery or open from the ambient lighting zone 3 blue circuit. |
DTC FAULT TRIGGER CONDITIONS
This pinpoint test is intended to diagnose the following
- Wiring, terminals or connectors
- Ambient lighting harness
- BCM-B
The Body Control Module B (BCM-B) supplies voltage and ground to the LEDs located in the floor console cup holders, console storage bin, driver and passenger scuff plates, both door map pockets and the front and rear footwells. The message center is used to cycle through the color combinations or to turn the ambient lighting feature off. There are 3 different color (red, blue and green) LEDs housed within each LED assembly.
This pinpoint test is intended to diagnose the following
- Wiring, terminals or connectors
- BCM-B
Diagnostic Overview
Diagnostics in this service information assume a certain skill level and knowledge of Ford-specific diagnostic practices. Refer to DIAGNOSTIC METHODS for information about these practices.
Refer to SYSTEM WIRING DIAGRAMS , Interior Lamps for additional information.
Normal Operation and Fault Conditions
Power is supplied to the pony projection lights through the Smart Junction Box (SJB) fuse 10 (15A). Based on the input status, the SJB supplies voltage to the pony projection lights. The pony projection lights have separate ground circuits.
| 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 pony projection light output because an excessive urrent draw exists (such as a short to ground). The SJB cannot enable the pony projection light 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 pony projection light 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 . |
| B2A39 - Puddle Lamp Output Circuit Open | An on-demand DTC that sets when the SJB detects an open on the pony projection light output circuit. |
| B2A3A - Puddle Lamp Output Circuit Short To Ground | A continuous and on-demand DTC that sets when the SJB detects a short to ground on the pony projection light output circuit. This DTC may also set as a result when the SJB fuse 10 (15A) has failed or is removed. |
DTC FAULT TRIGGER CONDITIONS
Diagnostics in this service information assume a certain skill level and knowledge of Ford-specific diagnostic practices. Refer to DIAGNOSTIC METHODS for information about these practices.
Refer to SYSTEM WIRING DIAGRAMS , Interior Lamps for additional information.
When the request from the instrument panel dimmer switch is detected, any door is opened, a correct unlock code from the keyless entry keypad or an unlock request from a programmed Remote Keyless Entry (RKE) transmitter is detected, the Smart Junction Box (SJB) supplies voltage to the pony projection lights.
- DTC B2A39 (Puddle Lamp Output Circuit Open) - an on-demand DTC that sets when the SJB detects a short to voltage from the pony projection light output circuit.