Ford Fiesta Quiz
Lighting

Interior Lighting - Diagnosis and Testing

In this manual: Lighting
Service Information — 27Suspension — 48Transmission — 9Brake System — 52Steering — 21Engine — 140Manual Transmission, Clutch, Transfer Case and Power Transfer Unit — 48Exhaust System — 6Fuel System — 21Climate Control System — 58Instrumentation and Warning Systems — 26Battery and Charging System — 20Infotainment Systems — 41Lighting — 29Power Distribution — 11Electronic Function Group — 30Body and Paint — 275Frame and Mounting — 3
~30min read

The diagnosis in this manual assumes a certain level of skill and knowledge of Ford-approved diagnostic procedures.
REFER TO: Diagnostic Methods (100-00 General Information, Description and Operation).

DTC Chart: BCM

DTC Chart


Trouble Code Description Action
B1091:12 Courtesy Lamp Circuit: Short to Battery GO to Pinpoint Test B
B1175:92 Driver Door Ajar Switch: Malfunction or Incorrect Operation GO to Pinpoint Test C
B1176:92 Passenger Door Ajar Sensor: Malfunction or Incorrect Operation GO to Pinpoint Test C
B11E9:92 Left Rear Door Ajar Sensor: Malfunction or Incorrect Operation GO to Pinpoint Test C
B11EA:92 Right Rear Door Ajar Sensor: Malfunction or Incorrect Operation GO to Pinpoint Test C
B1D14:11 Interior Lamp Circuit "B": Short to Ground GO to Pinpoint Test B

Symptom Chart

The diagnosis in this manual assumes a certain level of skill and knowledge of Ford-approved diagnostic procedures.
REFER TO: Diagnostic Methods (100-00 General Information, Description and Operation).

Symptom Chart: Interior Lighting

Symptom Chart


Condition Possible Sources Action
Module Does Not Respond to Scan Tool
  • Fuse
  • Wiring, Terminals or Connectors
  • Module
REFER TO: Communication Network (418-00 Communication Network, Diagnosis and Testing).
Lamps Do Not Illuminate When Door Is Open Refer to Pinpoint Test GO to Pinpoint Test A
One or More Interior Lamps Inoperative Refer to Pinpoint Test GO to Pinpoint Test B
All Lamps Stay On Refer to Pinpoint Test GO to Pinpoint Test C
Luggage compartment/cargo lamp inoperative or remains on Refer to Pinpoint Test GO to Pinpoint Test D
One or More Courtesy Lamps Inoperative Refer to Pinpoint Test GO to Pinpoint Test E
Battery Saver Does Not Turn Off After Timeout Refer to Pinpoint Test GO to Pinpoint Test F
Ambient lighting inoperative Refer to Pinpoint Test GO to Pinpoint Test G
Ambient lighting does not cycle through all color combinations. Refer to Pinpoint Test GO to Pinpoint Test H
Ambient lighting always on Refer to Pinpoint Test GO to Pinpoint Test I

Pinpoint Tests

Courtesy lamps do not illuminate with door open


Refer to Wiring Diagrams Cell 89 for schematic and connector information.

Normal Operation and Fault Symptoms


REFER TO: Interior Lighting - System Operation and Component Description (417-02 Interior Lighting, Description and Operation).

Possible Sources

  • Wiring, Terminals or Connectors
  • Door Ajar Switches (integrated into the door latches)
  • BCM

DIAGNOSTIC TEST A: DOME LAMPS DO NOT ILLUMINATE WITH DOOR OPEN
A1 CHECK THE VOLTAGE AT THE AMBIENT LIGHTING MODULE
  • Ignition OFF.
  • Use the dome lamp switch on the front overhead console to turn on the dome lamps.

Do the dome lamps illuminate?
Yes GO to A2
No GO to Pinpoint Test B
A2 CHECK THE OPERATION OF THE DOOR AJAR SWITCH
  • Disconnect the dome lamps from the front courtesy lamp.
  • Disconnect: Suspect door latch.

Does the indicator illuminate?
Yes For the front door, INSTALL a new front door latch.
REFER TO: Front Door Latch (501-14 Handles, Locks, Latches and Entry Systems, Removal and Installation). For the rear door, INSTALL a new rear door latch.
REFER TO: Rear Door Latch (501-14 Handles, Locks, Latches and Entry Systems, Removal and Installation).
No GO to A3
A3 CHECK THE DOOR AJAR SWITCH INPUT CIRCUIT FOR A SHORT TO GROUND
  • Disconnect: BCM C2280G.
  • Action:
    Click to display the connectors

    Left Front Door Ajar Switch


    Positive lead Measurement/Action Negative lead
    C525-3 Ground

    Click to display the connectors

    Right Front Door Ajar Switch


    Positive lead Measurement/Action Negative lead
    C609-6 Ground

    Click to display the connectors

    Left Rear Door Ajar Switch


    Positive lead Measurement/Action Negative lead
    C705-3 Ground

    Click to display the connectors

    Right Rear Door Ajar Switch


    Positive lead Measurement/Action Negative lead
    C805-6 Ground

Is the resistance greater than 10000 Ohms?
Yes GO to A4
No REPAIR the circuit.
A4 CHECK THE BCM (BODY CONTROL MODULE) FOR PROPER OPERATION
  • Disconnect and inspect all BCM connectors.
  • Repair:
    • corrosion (install new connector or terminals - clean module pins)
    • damaged or bent pins - install new terminals/pins
    • backed-out pins - install new pins as necessary
  • Reconnect the BCM connectors. Make sure they are fully seated and locked.
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes CHECK OASIS for any applicable technical service bulletins (TSBs). If a TSB exists for this concern, STOP this test and FOLLOW the TSB instructions. If no TSBs apply to this concern, INSTALL a new BCM.
REFER TO: Body Control Module (BCM) (419-10 Multifunction Electronic Modules, Removal and Installation).
No The system is currently operating correctly. The concern may have been caused by module connections. ADDRESS the root cause of any connector or terminal concerns. CLEAR the diagnostic trouble codes (DTCs).

One or more interior lamps inoperative


Refer to Wiring Diagrams Cell 89 for schematic and connector information.

Normal Operation and Fault Symptoms


REFER TO: Interior Lighting - System Operation and Component Description (417-02 Interior Lighting, Description and Operation).

Possible Sources

  • Fuse
  • Wiring, Terminals or Connectors
  • Courtesy Lamp
  • BCM

DTC Fault Trigger Conditions


Trouble Code Description Fault Trigger Conditions
B1091:12 Courtesy Lamp Circuit: Short to Battery Continuous DTC that is set on demand when the BCM detects a short to voltage on the interior lamp output circuit when it is energized.
B1D14:11 Interior Lamp Circuit "B": Short to Ground Continuous DTC that is set on demand when the BCM detects a short to ground on the battery saver output circuit when it is energized.

Visual Inspection and Preliminary Diagnosis

  • Make sure the interior lamps are serviceable.
  • BJB fuse F10 (15A).
  • BJB fuse F11 (15A).

DIAGNOSTIC TEST B: ONE OR MORE INTERIOR LAMPS INOPERATIVE
B1 CHECK THE OPERATION OF ALL LAMPS
  • Open the door.

Are all courtesy lamps inoperative?
Yes GO to B2
No If the front dome lamp is inoperative, GO to B8.
If the rear dome lamp is inoperative, GO to B11.
B2 CHECK THE OPERATION OF THE REQUEST LAMPS
  • Activate and observe all interior request lamps.

Are all request lamps inoperative?
Yes GO to B3
No GO to B14
B3 CHECK THE VOLTAGE AT THE FRONT LAMP
  • Ignition OFF.
  • Disconnect: Front dome lamp C931A and C931B (with overhead console).
  • Disconnect: Front dome lamp C931 (with anti-theft system).
  • Disconnect the front dome lamp C918 (without overhead console).
  • Disconnect the front courtesy lamp C929 (with sunroof).
  • The ignition is on.
  • Action:
    Click to display the connectors

    With overhead console


    Positive lead Measurement/Action Negative lead
    C931B-1 Ground

    Click to display the connectors

    With anti-theft system


    Positive lead Measurement/Action Negative lead
    C931-1 Ground

    Click to display the connectors

    Without overhead console


    Positive lead Measurement/Action Negative lead
    C918-3 Ground

    Click to display the connectors

    With sunroof


    Positive lead Measurement/Action Negative lead
    C929-3 Ground

Is the voltage greater than 11 volts?
Yes GO to B4
No GO to B6
B4 CHECK THE CONTROLLED LAMP GROUND FOR A SHORT TO VOLTAGE
  • Ignition OFF.
  • Disconnect: BCM C2280C.
  • The ignition is on.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C2280C-5 Ground

Is there voltage present?
Yes REPAIR the circuit.
No GO to B5
B5 CHECK THE FRONT LAMP GROUND CONTROL CIRCUIT FOR AN OPEN
  • Ignition OFF.
  • Action:
    Click to display the connectors

    With overhead console


    Positive lead Measurement/Action Negative lead
    C931A-1 C2280C-5

    Click to display the connectors

    With anti-theft system


    Positive lead Measurement/Action Negative lead
    C931-2 C2280C-5

    Click to display the connectors

    Without overhead console


    Positive lead Measurement/Action Negative lead
    C918-1 C2280C-5

    Click to display the connectors

    With sunroof


    Positive lead Measurement/Action Negative lead
    C929-2 C2280C-5

Is the resistance less than 3 ohms?
Yes GO TO B17
No REPAIR the circuit.
B6 CHECK THE DOME LAMP VOLTAGE CIRCUIT FOR AN OPEN
  • Ignition OFF.
  • Disconnect: BCM C2280C.
  • Disconnect: Front dome lamp C931A and C931B (with overhead console).
  • Disconnect: Front dome lamp C931 (with anti-theft system).
  • Disconnect the front dome lamp C918 (without overhead console).
  • Disconnect the front courtesy lamp C929 (with sunroof).
  • Action:
    Click to display the connectors

    With overhead console


    Positive lead Measurement/Action Negative lead
    C931B-1 C2280C-14

    Click to display the connectors

    With anti-theft system


    Positive lead Measurement/Action Negative lead
    C931-1 C2280C-14

    Click to display the connectors

    Without overhead console


    Positive lead Measurement/Action Negative lead
    C918-3 C2280C-14

    Click to display the connectors

    With sunroof


    Positive lead Measurement/Action Negative lead
    C929-3 C2280C-14

Is the resistance less than 3 ohms?
Yes GO to B7
No REPAIR the circuit.
B7 CHECK THE DOME LAMP VOLTAGE CIRCUIT FOR A SHORT TO GROUND
  • Disconnect: Rear dome lamp C932A and C932B (without map lamps).
  • Disconnect: Rear dome lamp C932 (with map lamps).
  • Disconnect: Cargo lamp C489.
  • Disconnect: Glove box lamp C254.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C2280C-14 Ground

Is the resistance greater than 10000 Ohms?
Yes GO TO B17
No REPAIR the circuit.
B8 CHECK THE FRONT LAMP
  • Close the door.
  • Ignition OFF.
  • Disconnect: Front dome lamp C931A and C931B (with overhead console).
  • Disconnect: Front dome lamp C931 (with anti-theft system).
  • Disconnect the front dome lamp C918 (without overhead console).
  • Disconnect the front courtesy lamp C929 (with sunroof).
  • The ignition is on.
  • Open the door.
  • Action:
    Click to display the connectors

    With overhead console


    Positive lead Measurement/Action Negative lead
    C931B-1 C931A-1

    Click to display the connectors

    With anti-theft system


    Positive lead Measurement/Action Negative lead
    C931-1 C931-2

    Click to display the connectors

    Without overhead console


    Positive lead Measurement/Action Negative lead
    C918-3 C918-1

    Click to display the connectors

    With sunroof


    Positive lead Measurement/Action Negative lead
    C929-3 C929-2

Is the voltage greater than 11 volts?
Yes GO to B9
No GO to B10
B9 CHECK THE FRONT FLOOD LAMP
  • Replace with a known good bulb and recheck the dome lamp operation.

Does the front dome lamp operate correctly?
Yes REMOVE the known good bulb. INSTALL a new front dome lamp bulb.
No INSTALL a new front dome lamp.
B10 CHECK THE FRONT LAMP GROUND CONTROL CIRCUIT FOR A SHORT TO GROUND
  • Ignition OFF.
  • Disconnect: BCM C2280C.
  • Action:
    Click to display the connectors

    With overhead console


    Positive lead Measurement/Action Negative lead
    C931A-1 C2280C-5

    Click to display the connectors

    With anti-theft system


    Positive lead Measurement/Action Negative lead
    C931-2 C2280C-5

    Click to display the connectors

    Without overhead console


    Positive lead Measurement/Action Negative lead
    C918-1 C2280C-5

    Click to display the connectors

    With sunroof


    Positive lead Measurement/Action Negative lead
    C929-2 C2280C-5

Is the resistance less than 3 ohms?
Yes GO TO B17
No REPAIR the circuit.
B11 CHECK THE REAR PLASTIC DOME LAMP
  • Close the door.
  • Ignition OFF.
  • Disconnect: Rear dome lamp C932A and C932B (without map lamps).
  • Disconnect: Rear dome lamp C932 (with map lamps).
  • The ignition is on.
  • Open the door.
  • Action:
    Click to display the connectors

    Without map lamps


    Positive lead Measurement/Action Negative lead
    C932A-1 C932B-1

    Click to display the connectors

    With map lamps


    Positive lead Measurement/Action Negative lead
    C932-3 C932-1

Is the voltage greater than 11 volts?
Yes GO to B12
No GO to B13
B12 CHECK THE REAR DOME LAMP BULBS
  • Replace with a known good bulb and recheck the dome lamp operation.

Does the front dome lamp operate correctly?
Yes REMOVE the known good bulb. INSTALL a new rear dome lamp bulb.
No INSTALL a new rear dome lamp.
B13 CHECK THE REAR DOME LAMP GROUND CONTROL CIRCUIT FOR A SHORT TO GROUND
  • Ignition OFF.
  • Disconnect: BCM C2280C.
  • Action:
    Click to display the connectors

    Without map lamps


    Positive lead Measurement/Action Negative lead
    C932B-1 C2280C-5

    Click to display the connectors

    With map lamps


    Positive lead Measurement/Action Negative lead
    C932-1 C2280C-5

Is the resistance less than 3 ohms?
Yes GO TO B17
No REPAIR the circuit.
B14 BYPASS THE BCM (BODY CONTROL MODULE) GROUND CHECK
  • Ignition OFF.
  • Disconnect: BCM C2280C.
  • Connect a fused jumper wire:
    Click to display connectors
    Positive lead Measurement/Action Negative lead
    C2280C-5 Ground

    Click to display connectors
    Positive lead Measurement/Action Negative lead
    C2280C-14 Battery positive
  • The ignition is on.
  • Open any door.

Does the indicator illuminate?
Yes REMOVE the fusible link. GO to B17.
No REMOVE the fusible link. GO to B15
B15 CHECK THE LAMP CONTROL CIRCUIT FOR A SHORT TO GROUND OR A SHORT TO VOLTAGE
  • Ignition OFF.
  • Disconnect: Front dome lamp C931A and C931B (with overhead console).
  • Disconnect: Front dome lamp C931 (with anti-theft system).
  • Disconnect the front dome lamp C918 (without overhead console).
  • Disconnect the front courtesy lamp C929 (with sunroof).
  • The ignition is on.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C2280C-5 Ground

Is there voltage present?
Yes REPAIR the circuit
No GO TO B16
B16 CHECK THE INTERIOR LAMP GROUND CONTROL CIRCUIT FOR AN OPEN
  • Ignition OFF.
  • Action:
    Click to display the connectors

    With overhead console


    Positive lead Measurement/Action Negative lead
    C931A-1 C2280C-5

    Click to display the connectors

    With anti-theft system


    Positive lead Measurement/Action Negative lead
    C931-2 C2280C-5

    Click to display the connectors

    Without overhead console


    Positive lead Measurement/Action Negative lead
    C918-1 C2280C-5

    Click to display the connectors

    With sunroof


    Positive lead Measurement/Action Negative lead
    C929-2 C2280C-5

Is the resistance less than 5 ohms?
Yes GO TO B17
No REPAIR the circuit.
B17 CHECK THE BCM (BODY CONTROL MODULE) OPERATION
  • Disconnect and inspect all BCM connectors.
  • Repair:
    • corrosion (install new connector or terminals - clean module pins)
    • damaged or bent pins - install new terminals/pins
    • backed-out pins - install new pins as necessary
  • Reconnect the BCM connectors. Make sure they are fully seated and locked.
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes CHECK OASIS for any applicable technical service bulletins (TSBs). If a TSB exists for this concern, STOP this test and FOLLOW the TSB instructions. If no TSBs apply to this concern, INSTALL a new BCM.
REFER TO: Body Control Module (BCM) (419-10 Multifunction Electronic Modules, Removal and Installation).
No The system is currently operating correctly. The concern may have been caused by module connections. ADDRESS the root cause of any connector or terminal concerns. CLEAR the diagnostic trouble codes (DTCs).

All courtesy lamps remain on continuously


Refer to Wiring Diagrams Cell 89 for schematic and connector information.

Normal Operation and Fault Symptoms


REFER TO: Interior Lighting - System Operation and Component Description (417-02 Interior Lighting, Description and Operation).

Possible Sources

  • Wiring, Terminals or Connectors
  • Door Ajar Switches (integrated into the door latches)
  • BCM

DTC Fault Trigger Conditions


Trouble Code Description Fault Trigger Conditions
B1175:92 Driver Door Ajar Switch: Malfunction or Incorrect Operation On-demand DTC that is set when the BCM detects an open in the left front door ajar circuit during BCM self-test.
B1176:92 Passenger Door Ajar Sensor: Malfunction or Incorrect Operation On-demand DTC that is set when the BCM detects an open circuit for the right front door ajar switch during the BCM self-test.
B11E9:92 Left Rear Door Ajar Sensor: Malfunction or Incorrect Operation On-demand DTC that is set when the BCM detects an open circuit for the left rear door ajar switch during the BCM self-test.
B11EA:92 Right Rear Door Ajar Sensor: Malfunction or Incorrect Operation On-demand DTC that is set when the BCM detects an open circuit for the right rear door ajar switch during the BCM self-test.

DIAGNOSTIC TEST C: ALL DOME LAMPS REMAIN ON CONTINUOUSLY
C1 CHECK THE DOOR AJAR SWITCH PARAMETER IDENTIFICATION (PIDS)
  • The ignition is on.
  • Using a scan tool, review the BCM parameter identifications (PIDs).
  • Monitor the BCM DOOR_SW_DRVR, DOOR_SW_PSGR, DOOR_SW_LR and DOOR_SW_RR parameter identifications (PIDs) while opening and closing all the doors.

Do all the door ajar switch PID values match the door positions?
Yes GO to C5
No GO to C2
C2 BYPASS THE SUSPECTED DOOR LATCH
  • Disconnect: Suspect door switch.
  • Install the fused jumper wire:
    Click to display connectors

    Left Front Door Ajar Switch


    Positive lead Measurement/Action Negative lead
    C525-3 C525-5

    Click to display the connectors

    Right Front Door Ajar Switch


    Positive lead Measurement/Action Negative lead
    C609-6 C609-4

    Click to display the connectors

    Left Rear Door Ajar Switch


    Positive lead Measurement/Action Negative lead
    C705-3 C705-5

    Click to display the connectors

    Right Rear Door Ajar Switch


    Positive lead Measurement/Action Negative lead
    C805-6 C805-4
  • Using a scan tool, review the BCM parameter identifications (PIDs).
  • Monitor the BCM DOOR_SW_DRVR, DOOR_SW_PSGR, DOOR_SW_LR and DOOR_SW_RR parameter identifications (PIDs).

Does the PID indicate that the door in question is closed?
Yes REMOVE the fusible link. For the front door, INSTALL a new front door latch.
Refer to: Front Door Latch (501-14 Door Handles, Locks, Latches and Entry Systems, Removal and Installation). REMOVE the fusible link. For the rear door, INSTALL a new rear door latch.
Refer to: Rear Door Latch (501-14 Door Handles, Locks, Latches and Entry Systems, Removal and Installation).
No REMOVE the fusible link. GO to C3
C3 BYPASS THE DOOR LATCH GROUND CIRCUIT
  • Install the fused jumper wire:
    Click to display connectors

    Left Front Door Ajar Switch


    Positive lead Measurement/Action Negative lead
    C525-3 Ground

    Click to display the connectors

    Right Front Door Ajar Switch


    Positive lead Measurement/Action Negative lead
    C609-6 Ground

    Click to display the connectors

    Left Rear Door Ajar Switch


    Positive lead Measurement/Action Negative lead
    C705-3 Ground

    Click to display the connectors

    Right Rear Door Ajar Switch


    Positive lead Measurement/Action Negative lead
    C805-6 Ground
  • Monitor the BCM DOOR_SW_DRVR, DOOR_SW_PSGR, DOOR_SW_LR and DOOR_SW_RR parameter identifications (PIDs).

Does the PID indicate that the door in question is closed?
Yes REMOVE the fusible link. REPAIR the faulty door latch ground circuit for an open.
No REMOVE the fused jumper wire. GO to C4.
C4 CHECK THE SUSPECTED DOOR AJAR SWITCH INPUT CIRCUIT FOR AN OPEN
  • Disconnect: BCM C2280G.
  • Action:
    Click to display the connectors

    Left Front Door Ajar Switch


    Positive lead Measurement/Action Negative lead
    C525-3 C2280G-19

    Click to display the connectors

    Right Front Door Ajar Switch


    Positive lead Measurement/Action Negative lead
    C609-6 C2280G-20

    Click to display the connectors

    Left Rear Door Ajar Switch


    Positive lead Measurement/Action Negative lead
    C705-3 C2280G-21

    Click to display the connectors

    Right Rear Door Ajar Switch


    Positive lead Measurement/Action Negative lead
    C805-6 C2280G-22

Is the resistance less than 3 ohms?
Yes GO TO C7
No REPAIR the faulty door ajar switch input circuit.
C5 ISOLATE THE BCM (BODY CONTROL MODULE)
  • Ignition OFF.
  • Disconnect: BCM C2280C.
  • The ignition is on.

Do the courtesy lamps remain on?
Yes GO to C6
No GO TO C7
C6 CHECK THE INTERIOR LAMP CONTROL CIRCUIT TO GROUND FOR A SHORT TO GROUND
  • Ignition OFF.
  • Disconnect: Front dome lamp C931A and C931B (with overhead console).
  • Disconnect: Front dome lamp C931 (with anti-theft system).
  • Disconnect the front dome lamp C918 (without overhead console).
  • Disconnect the front courtesy lamp C929 (with sunroof).
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C2280C-5 Ground

Is the resistance greater than 10000 Ohms?
Yes INSTALL a new left front/front courtesy lamp.
No REPAIR the circuit.
C7 CHECK THE BCM (BODY CONTROL MODULE) FOR PROPER OPERATION
  • Disconnect and inspect all BCM connectors.
  • Repair:
    • corrosion (install new connector or terminals - clean module pins)
    • damaged or bent pins - install new terminals/pins
    • backed-out pins - install new pins as necessary
  • Reconnect the BCM connectors. Make sure they are fully seated and locked.
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes CHECK OASIS for any applicable technical service bulletins (TSBs). If a TSB exists for this concern, STOP this test and FOLLOW the TSB instructions. If no TSBs apply to this concern, INSTALL a new BCM.
REFER TO: Body Control Module (BCM) (419-10 Multifunction Electronic Modules, Removal and Installation).
No The system is currently operating correctly. The concern may have been caused by module connections. ADDRESS the root cause of any connector or terminal concerns. CLEAR the diagnostic trouble codes (DTCs).

Luggage compartment/cargo lamp inoperative or stays on


Refer to Wiring Diagrams Cell 89 for schematic and connector information.

Normal Operation and Fault Symptoms


REFER TO: Interior Lighting - System Operation and Component Description (417-02 Interior Lighting, Description and Operation).

Possible Sources

  • Wiring, Terminals or Connectors

DIAGNOSTIC TEST D: LUGGAGE COMPARTMENT/CARGO AREA LAMP INOPERATIVE OR REMAINS ON
D1 DETERMINE IF THE LAMP IS ON WITH THE LIFTGATE/LUGGAGE COMPARTMENT LID CLOSED
  • The ignition is on.
  • Make sure the liftgate or luggage compartment lid is fully latched, and observe the cargo lamp.

Is the cargo lamp on?
Yes GO to D2
No GO to D3
D2 CHECK THE CARGO LAMP GROUND CIRCUIT FOR A SHORT TO GROUND
  • Disconnect: Liftgate/Luggage Compartment Latch C4223.

Does the cargo lamp remain on?
Yes REPAIR the circuit.
No For a 4-door vehicle, INSTALL a new luggage compartment lid latch.
Refer to: Luggage Compartment Lid Latch (501-14 Door Handles, Locks, Latches and Entry Systems, Removal and Installation). For a 5-door vehicle, INSTALL a new liftgate latch.
Refer to: Liftgate Latch (501-14 Door Handles, Locks, Latches and Entry Systems, Removal and Installation).
D3 CHECK THE OPERATION OF THE REQUEST LAMPS
  • Activate and observe all interior request lamps.

Are the interior request lamps operating correctly?
Yes GO to D4
No GO to Pinpoint Test E
D4 CHECK THE VOLTAGE AT THE CARGO LAMP
  • Disconnect: Cargo lamp C489.
  • The ignition is on.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C489-1 Ground

Is the voltage greater than 11 volts?
Yes GO to D5
No REPAIR the cargo lamp power supply circuit for an open.
D5 ISOLATE THE CARGO LAMP
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C489-1 C489-2

Is the voltage greater than 11 volts?
Yes INSTALL a new cargo lamp.
No GO to D6
D6 CHECK THE CARGO LAMP GROUND CIRCUIT FOR AN OPEN
  • Ignition OFF.
  • Disconnect: Liftgate/Luggage Compartment Latch C4223.
  • The ignition is on.
  • Connect a fused jumper wire:
    Click to display connectors
    Positive lead Measurement/Action Negative lead
    C4223-4 Ground

Does the cargo lamp illuminate?
Yes REMOVE the fusible link. GO to D7
No REMOVE the fuse jumper wire. REPAIR the circuit.
D7 CHECK THE LIFTGATE LATCH GROUND CIRCUIT FOR AN OPEN
  • Connect a fused jumper wire:
    Click to display connectors
    Positive lead Measurement/Action Negative lead
    C4223-4 C4223-2

Does the cargo lamp illuminate?
Yes REMOVE the fusible link.
For a 4-door vehicle, INSTALL a new luggage compartment lid latch.
Refer to: Luggage Compartment Lid Latch (501-14 Door Handles, Locks, Latches and Entry Systems, Removal and Installation). For a 5-door vehicle, INSTALL a new liftgate latch.
Refer to: Liftgate Latch (501-14 Door Handles, Locks, Latches and Entry Systems, Removal and Installation).
No REMOVE the fuse jumper wire. REPAIR the circuit.

One or more request lamps inoperative


Refer to Wiring Diagrams Cell 89 for schematic and connector information.

Normal Operation and Fault Symptoms


REFER TO: Interior Lighting - System Operation and Component Description (417-02 Interior Lighting, Description and Operation).

Possible Sources

  • Wiring, Terminals or Connectors
  • Demand Lamp

Visual Inspection and Preliminary Diagnosis

  • Inspect the bulbs and make sure they are in good condition.
  • Check the operation of the courtesy lamp.
  • Inspect the interior lamp for damage.

DIAGNOSTIC TEST E: ONE OR MORE REQUEST LAMPS INOPERATIVE
E1 CHECK THE OPERATION OF THE COURTESY LAMP
  • The ignition is on.
  • Open any door and observe the interior courtesy lamps.

Does the courtesy lamp illuminate?
Yes If the cargo lamp is inoperative, GO to test D.
If the front dome lamp or map lamp is inoperative, GO to E4.
If the rear dome lamp or map lamp is inoperative, GO to E5.
If the glove box lamp is inoperative, GO to E2.
No GO to Pinpoint Test B
E2 CHECK THE GLOVE BOX LAMP VOLTAGE SUPPLY CIRCUIT FOR AN OPEN
  • Ignition OFF.
  • Disconnect: Glove box lamp C254.
  • The ignition is on.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C254-1 Ground

Is the voltage greater than 11 volts?
Yes GO to E3
No REPAIR the circuit.
E3 CHECK THE GLOVE BOX LAMP GROUND CIRCUIT FOR AN OPEN
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C254-1 C254-2

Is the voltage greater than 11 volts?
Yes INSTALL a new glove box lamp.
No REPAIR the circuit.
E4 CHECK THE FRONT DOME LAMP GROUND CIRCUIT FOR AN OPEN
  • Ignition OFF.
  • Disconnect: Front dome lamp C931A and C931B (with overhead console).
  • Disconnect: Front dome lamp C931 (with anti-theft system).
  • Disconnect the front dome lamp C918 (without overhead console).
  • Disconnect the front courtesy lamp C929 (with sunroof).
  • The ignition is on.
  • Action:
    Click to display the connectors

    With overhead console


    Positive lead Measurement/Action Negative lead
    C931A-2 Ground

    Click to display the connectors

    With anti-theft system


    Positive lead Measurement/Action Negative lead
    C931-3 Ground

    Click to display the connectors

    Without overhead console


    Positive lead Measurement/Action Negative lead
    C918-2 Ground

    Click to display the connectors

    With sunroof


    Positive lead Measurement/Action Negative lead
    C929-4 Ground

Is the resistance less than 3 ohms?
Yes INSTALL a new dome lamp for the lamp in question.
No REPAIR the circuit.
E5 CHECK THE REAR DOME LAMP GROUND CIRCUIT FOR AN OPEN
  • Ignition OFF.
  • Disconnect: Rear dome lamp C932A and C932B (without map lamps).
  • Disconnect: Rear dome lamp C932 (with map lamps).
  • The ignition is on.
  • Action:
    Click to display the connectors

    Without map lamps


    Positive lead Measurement/Action Negative lead
    C932B-2 Ground

    Click to display the connectors

    With map lamps


    Positive lead Measurement/Action Negative lead
    C932-2 Ground

Is the resistance less than 3 ohms?
Yes INSTALL a new dome lamp for the lamp in question.
No REPAIR the circuit.

Battery Saver Does Not Turn Off After Timeout


Refer to Wiring Diagrams Cell 89 for schematic and connector information.

Normal Operation and Fault Symptoms


REFER TO: Interior Lighting - System Operation and Component Description (417-02 Interior Lighting, Description and Operation).

Possible Sources

  • Wiring, Terminals or Connectors
  • BCM

DIAGNOSTIC TEST F: BATTERY SAVER DOES NOT DEACTIVATE AFTER TIMEOUT
F1 CHECK THE REQUEST LAMP VOLTAGE SUPPLY CIRCUIT FOR A SHORT TO VOLTAGE
  • Ignition OFF.
  • Disconnect: BCM C2280C.
  • Turn on any request lamp (map or glove box).

Is the request lamp on?
Yes REPAIR the circuit.
No GO to F2
F2 CHECK THE BCM (BODY CONTROL MODULE) OPERATION
  • Disconnect and inspect all BCM connectors.
  • Repair:
    • corrosion (install new connector or terminals - clean module pins)
    • damaged or bent pins - install new terminals/pins
    • backed-out pins - install new pins as necessary
  • Reconnect the BCM connectors. Make sure they are fully seated and locked.
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes CHECK OASIS for any applicable technical service bulletins (TSBs). If a TSB exists for this concern, STOP this test and FOLLOW the TSB instructions. If no TSBs apply to this concern, INSTALL a new BCM.
REFER TO: Body Control Module (BCM) (419-10 Multifunction Electronic Modules, Removal and Installation).
No The system is currently operating correctly. The concern may have been caused by module connections. ADDRESS the root cause of any connector or terminal concerns. CLEAR the diagnostic trouble codes (DTCs).

Ambient lighting inoperative


Refer to Wiring Diagrams Cell 89 for schematic and connector information.

Normal Operation and Fault Symptoms


REFER TO: Interior Lighting - System Operation and Component Description (417-02 Interior Lighting, Description and Operation).

Possible Sources

  • Wiring, Terminals or Connectors
  • BCM
  • Ambient Lighting Module

DIAGNOSTIC TEST G: AMBIENT LIGHTING INOPERATIVE
G1 CHECK THE VOLTAGE AT THE AMBIENT LIGHTING MODULE
  • Ignition OFF.
  • Disconnect: Ambient Lighting Module C3347.
  • The ignition is on.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C3347-1 Ground

Is the voltage greater than 11 volts?
Yes GO to G4
No GO to G2
G2 CHECK THE AMBIENT LIGHTING MODULE VOLTAGE SUPPLY CIRCUIT FOR A SHORT TO GROUND
  • Ignition OFF.
  • Disconnect: BCM C2280E.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C3347-1 Ground

Is the resistance greater than 10000 Ohms?
Yes GO to G3
No REPAIR the circuit.
G3 CHECK THE AMBIENT LIGHTING MODULE VOLTAGE SUPPLY CIRCUIT FOR AN OPEN
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C3347-1 C2280E-23

Is the resistance less than 3 ohms?
Yes GO to G11
No REPAIR the circuit.
G4 CHECK THE AMBIENT LIGHTING SWITCH OUTPUT CIRCUIT
  • While pressing and releasing the ambient lighting switch, measure:
    Click to display connectors
    Positive lead Measurement/Action Negative lead
    C3347-2 Ground

Is the voltage greater than 11 V with the switch pressed and 0 V with the switch released?
Yes GO to G5
No If voltage is always present, GO to G7.
If no voltage is present, GO to G8.
G5 CHECK THE AMBIENT LIGHTING MODULE GROUND CIRCUIT FOR AN OPEN
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C3347-1 C3347-8

Is the voltage greater than 11 volts?
Yes GO to G6
No REPAIR the circuit.
G6 CHECK THE AMBIENT LIGHTING WIRING HARNESS
  • Ignition OFF.
  • Using the diode test function, measure:
    Click to display connectors
    Positive lead Measurement/Action Negative lead
    C3347-5 C3347-4
    C3347-6 C3347-4
    C3347-7 C3347-4

Does the indicator show the circuit is good?
Yes GO to G10
No REPAIR the circuit or INSTALL a new ambient lighting wiring harness.
G7 CHECK THE AMBIENT LIGHTING SWITCH OUTPUT CIRCUIT FOR A SHORT TO VOLTAGE
  • Ignition OFF.
  • Disconnect: Exterior Lighting Switch C2401.
  • The ignition is on.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C3347-2 Ground

Is there voltage present?
Yes REPAIR the circuit.
No INSTALL a new exterior lighting/seat heater switch.
G8 CHECK THE AMBIENT LIGHTING SWITCH VOLTAGE SUPPLY CIRCUIT FOR AN OPEN
  • Ignition OFF.
  • Connect: Ambient Lighting Module C3347.
  • Disconnect: Exterior Lighting Switch C2401.
  • The ignition is on.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C2401-2 Ground

Is the voltage greater than 11 volts?
Yes GO to G9
No REPAIR the circuit.
G9 AMBIENT LIGHTING SWITCH BYPASS
  • Connect and remove the fuse jumper wire:
    Click to display connectors
    Positive lead Measurement/Action Negative lead
    C2401-1 C2401-2

Do the ambient light-emitting diodes (LEDs) illuminate and cycle through colors each time the jumper is connected and removed?
Yes INSTALL a new exterior lighting/seat heater switch.
No REPAIR the ambient lighting switch ground circuit for an open.
G10 CHECK AMBIENT LIGHTING MODULE OPERATION
  • Disconnect and inspect the ambient lighting module connector.
  • Repair:
    • corrosion (install new connector or terminals - clean module pins)
    • damaged or bent pins - install new terminals/pins
    • backed-out pins - install new pins as necessary
  • Reconnect the ambient lighting module connector. Make sure it is properly seated and clicks into place.
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, STOP this test and FOLLOW the TSB instructions. If no TSB applies to this concern, INSTALL a new ambient lighting module.
No The system is currently operating correctly. The concern may have been caused by module connections. ADDRESS the root cause of any connector or terminal concerns. CLEAR the diagnostic trouble codes (DTCs).
G11 CHECK BCM (BODY CONTROL MODULE) OPERATION
  • Disconnect and inspect all BCM connectors.
  • Repair:
    • corrosion (install new connector or terminals - clean module pins)
    • damaged or bent pins - install new terminals/pins
    • backed-out pins - install new pins as necessary
  • Reconnect the BCM connectors. Make sure they are fully seated and locked.
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes CHECK OASIS for any applicable technical service bulletins (TSBs). If a TSB exists for this concern, STOP this test and FOLLOW the TSB instructions. If no TSBs apply to this concern, INSTALL a new BCM.
REFER TO: Body Control Module (BCM) (419-10 Multifunction Electronic Modules, Removal and Installation).
No The system is currently operating correctly. The concern may have been caused by module connections. ADDRESS the root cause of any connector or terminal concerns. CLEAR the diagnostic trouble codes (DTCs).

Ambient lighting does not cycle through all color variations


Refer to Wiring Diagrams Cell 89 for schematic and connector information.

Normal Operation and Fault Symptoms


REFER TO: Interior Lighting - System Operation and Component Description (417-02 Interior Lighting, Description and Operation).

Possible Sources

  • Wiring, Terminals or Connectors
  • Ambient Lighting Switch
  • Ambient lighting wiring harness
  • Ambient Lighting Module

DIAGNOSTIC TEST H: AMBIENT LIGHTING DOES NOT CYCLE THROUGH ALL COLOR COMBINATIONS
H1 CHECK THE AMBIENT LIGHTING SWITCH OUTPUT CIRCUIT
  • Ignition OFF.
  • Disconnect: Ambient Lighting Module C3347.
  • The ignition is on.
  • While pressing and releasing the ambient lighting switch, measure:
    Click to display connectors
    Positive lead Measurement/Action Negative lead
    C3347-2 Ground

Is the voltage greater than 11 V with the switch pressed and 0 V with the switch released?
Yes GO to H2
No If voltage is always present, GO to H3.
If voltage is not present, GO to H4.
H2 CHECK THE AMBIENT LIGHTING WIRING HARNESS
  • Ignition OFF.
  • Using the diode test function, measure:
    Click to display connectors
    Positive lead Measurement/Action Negative lead
    C3347-5 C3347-4
    C3347-6 C3347-4
    C3347-7 C3347-4

Does the indicator show the circuit is good?
Yes GO to H6
No REPAIR the circuit or INSTALL a new ambient lighting wiring harness.
H3 CHECK THE AMBIENT LIGHTING SWITCH OUTPUT CIRCUIT FOR A SHORT TO VOLTAGE
  • Ignition OFF.
  • Disconnect: Exterior Lighting Switch C2401.
  • The ignition is on.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C3347-2 Ground

Is there voltage present?
Yes REPAIR the circuit.
No INSTALL a new exterior lighting/seat heater switch.
H4 CHECK THE AMBIENT LIGHTING SWITCH VOLTAGE SUPPLY CIRCUIT FOR AN OPEN
  • Ignition OFF.
  • Connect: Ambient Lighting Module C3347.
  • Disconnect: Exterior Lighting Switch C2401.
  • The ignition is on.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C2401-2 Ground

Is the voltage greater than 11 volts?
Yes GO to H5
No REPAIR the circuit.
H5 AMBIENT LIGHTING SWITCH BYPASS
  • Connect and remove the fuse jumper wire:
    Click to display connectors
    Positive lead Measurement/Action Negative lead
    C2401-1 C2401-2

Do the ambient light-emitting diodes (LEDs) illuminate and cycle through colors each time the jumper is connected and removed?
Yes INSTALL a new exterior lighting/seat heater switch.
No REPAIR the ambient lighting switch ground circuit for an open.
H6 CHECK AMBIENT LIGHTING MODULE OPERATION
  • Disconnect and inspect the ambient lighting module connector.
  • Repair:
    • corrosion (install new connector or terminals - clean module pins)
    • damaged or bent pins - install new terminals/pins
    • backed-out pins - install new pins as necessary
  • Reconnect the ambient lighting module connector. Make sure it is properly seated and clicks into place.
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, STOP this test and FOLLOW the TSB instructions. If no TSB applies to this concern, INSTALL a new ambient lighting module.
No The system is currently operating correctly. The concern may have been caused by module connections. ADDRESS the root cause of any connector or terminal concerns. CLEAR the diagnostic trouble codes (DTCs).

Ambient lighting always on


Refer to Wiring Diagrams Cell 89 for schematic and connector information.

Normal Operation and Fault Symptoms


REFER TO: Interior Lighting - System Operation and Component Description (417-02 Interior Lighting, Description and Operation).

Possible Sources

  • Wiring, Terminals or Connectors
  • Ambient LED Lighting
  • Ambient Lighting Module

DIAGNOSTIC TEST I: AMBIENT LIGHTING ALWAYS ON
NOTE: Under certain conditions the ambient lighting system remains active for up to 10 minutes after the ignition is turned off or a door is opened. Make sure the battery saver function operates correctly before continuing diagnosis.
I1 CHECK BCM (BODY CONTROL MODULE) AMBIENT LIGHTING SYSTEM OUTPUT CIRCUIT FOR A SHORT TO VOLTAGE
  • Ignition OFF.
  • Disconnect: BCM C2280E.
  • The ignition is on.

Does the ambient lighting remain on?
Yes REPAIR the circuit.
No GO to I2.
I2 CHECK BCM (BODY CONTROL MODULE) OPERATION
  • Disconnect and inspect all BCM connectors.
  • Repair:
    • corrosion (install new connector or terminals - clean module pins)
    • damaged or bent pins - install new terminals/pins
    • backed-out pins - install new pins as necessary
  • Reconnect the BCM connectors. Make sure they are fully seated and locked.
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes CHECK OASIS for any applicable technical service bulletins (TSBs). If a TSB exists for this concern, STOP this test and FOLLOW the TSB instructions. If no TSBs apply to this concern, INSTALL a new BCM.
REFER TO: Body Control Module (BCM) (419-10 Multifunction Electronic Modules, Removal and Installation).
No The system is currently operating correctly. The concern may have been caused by module connections. ADDRESS the root cause of any connector or terminal concerns. CLEAR the diagnostic trouble codes (DTCs).

Test yourself

A quick Ford Fiesta quiz: every answer comes with an explanation and a link to the manual page.