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Pinpoint Test J: The Ambient Lighting Is Inoperative

WARNING: This page is about a different car, the 2010 Mercury Mariner and 2010 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
  1. J1 CHECK FOR VOLTAGE TO THE AMBIENT LIGHTING MODULE 
    • Ignition OFF.
    • Disconnect: Ambient Lighting Module C3351.
    • Ignition ON.
    • Measure the voltage between the ambient lighting module C3351-1, circuit CBX07 (GN/RD), harness side and ground.
      Fig 1: Measuring Voltage Between Ambient Lighting Module C3351-1, Circuit CBX07 (GN/RD), Harness Side And Ground
      G06390908Courtesy of FORD MOTOR CO.
    • Is the voltage greater than 10 volts? 
    • Yes:  GO to J2  .
    • No:  REPAIR circuit CBX07 (GN/RD) for an open. TEST the system for normal operation.
  2. J2 CHECK THE INPUT FROM THE AMBIENT LIGHTING SWITCH 
    • While pressing and releasing the ambient lighting switch, measure the voltage between the ambient lighting module C3351-2, circuit CLN54 (BN/YE), harness side and ground.
      Fig 2: Measuring Voltage Between Ambient Lighting Module C3351-2, Circuit CLN54 (BN/YE), Harness Side And Ground
      G06390909Courtesy of FORD MOTOR CO.
    • Is the voltage greater than 10 volts with the switch pressed and 0 volts with the switch released? 
    • Yes:  GO to J3  .
    • No:  If voltage is always present, GO to  J4.

      If no voltage is present, GO to  J5.

  3. J3 CHECK FOR VOLTAGE TO THE AMBIENT LIGHTING MODULE USING THE CONNECTOR GROUND 
    • Measure the voltage between the ambient lighting module C3351-1, circuit CBX07 (GN/RD), harness side and the ambient lighting module C3351-8, circuit GD908 (BK), harness side.
      Fig 3: Checking Voltage To Ambient Lighting Module Using Connector Ground
      G06390910Courtesy of FORD MOTOR CO.
    • Is the voltage greater than 10 volts? 
    • Yes:  GO to  J7.
    • No:  REPAIR circuit GD908 (BK) for an open. TEST the system for normal operation.
  4. J4 CHECK THE AMBIENT LIGHTING SWITCH INPUT CIRCUIT FOR A SHORT TO VOLTAGE 
    • Ignition OFF.
    • Disconnect: Ambient Lighting Switch C3350.
    • Ignition ON.
    • Measure the voltage between the ambient lighting module C3351-2, circuit CLN54 (BN/YE), harness side and ground.
      Fig 4: Measuring Voltage Between Ambient Lighting Module C3351-2, Circuit CLN54 (BN/YE), Harness Side And Ground
      G06390909Courtesy of FORD MOTOR CO.
    • Is any voltage present? 
    • Yes:  REPAIR circuit CLN54 (BN/YE) for a short to voltage. TEST the system for normal operation.
    • No:  INSTALL a new ambient lighting switch. REFER to AMBIENT LIGHTING SWITCH . TEST the system for normal operation.
  5. J5 CHECK FOR VOLTAGE TO THE AMBIENT LIGHTING SWITCH 
    • Ignition OFF.
    • Connect: Ambient Lighting Module C3351.
    • Disconnect: Ambient Lighting Switch C3350.
    • Ignition ON.
    • Measure the voltage between the ambient lighting switch C3350-2, circuit CBX07 (GN/RD), harness side and ground.
      Fig 5: Measuring Voltage Between Ambient Lighting Switch C3350-2, Circuit CBX07 (GN/RD), Harness Side And Ground
      G06390912Courtesy of FORD MOTOR CO.
    • Is the voltage greater than 10 volts? 
    • Yes:  GO to J6  .
    • No:  REPAIR CBX07 (GN/RD) for an open. TEST the system for normal operation.
  6. J6 BYPASS THE AMBIENT LIGHTING SWITCH 
    • Connect and remove a fused jumper wire between the ambient lighting switch C3350-2, circuit CBX07 (GN/RD), harness side and the ambient lighting switch C3350-6, circuit CLN54 (BN/YE), harness side.
      Fig 6: Connecting Fused Jumper Wire Between Ambient Lighting Switch C3350-2, Circuit CBX07 (GN/RD) And C3350-6, Circuit CLN54 (BN/YE)
      G06390913Courtesy of FORD MOTOR CO.
    • Do the ambient LEDs illuminate and cycle through a color change each time the jumper wire is connected and removed? 
    • Yes:  INSTALL a new ambient lighting switch. REFER to AMBIENT LIGHTING SWITCH . TEST the system for normal operation.
    • No:  REPAIR circuit CLN54 (BN/YE) for an open. TEST the system for normal operation.
  7. J7 CHECK THE AMBIENT LIGHTING HARNESS 
    • Ignition OFF.
    • Check any of the diode circuits between the ambient lighting module, harness side as follows:
      CONNECTOR-PIN REFERENCE CHART

      Connector-Pin/Circuit Connector-Pin/Circuit
      C3351-5
      CLN45 (GN)      		 C3351-4
      RLN44 (BN)
      C3351-6
      CLN46 (BU)      		 C3351-4
      RLN44 (BN)
      C3351-7
      CLN44 (OG)      		 C3351-4
      RLN44 (BN)
      Fig 7: Checking Diode Circuits Between Ambient Lighting Module, Harness Side
      G06390914Courtesy of FORD MOTOR CO.
    • Does the meter indicate the circuit is good? 
    • Yes:  GO to J8  .
    • No:  REPAIR or INSTALL a new ambient lighting harness. TEST the system for normal operation.
  8. J8 CHECK FOR CORRECT AMBIENT LIGHTING MODULE OPERATION 
    • Disconnect the ambient lighting module connector.
    • Check for:
      • corrosion
      • damaged pins
      • pushed-out pins
    • Connect the ambient lighting module connector and make sure it seats correctly.
    • Operate the system and verify the concern is still present.
    • Is the concern still present? 
    • Yes:  INSTALL a new ambient lighting module. REFER to AMBIENT LIGHTING MODULE . TEST the system for normal operation.

      If the concern is still present, INSTALL the original ambient lighting module. INSTALL a new ambient lighting harness. TEST the system for normal operation.

    • No:  The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.
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