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Pinpoint Test P : The Keyless Entry Keypad Illumination Is Inoperative

  1. P1 CHECK THE KEYLESS ENTRY KEYPAD OPERATION

    • Press the 7/8 and 9/0 buttons simultaneously on the keyless entry keypad.

    Do the doors lock using the keyless entry keypad? 

    Yes  VERIFY the BCM fuse 18 (10A) is OK. If OK, GO to  P2. If not OK, REFER to the OEM ELECTRICAL WIRING DIAGRAM INTRODUCTION to identify the possible causes of the circuit short.
    No  GO to Pinpoint Test O .

  2. P2 CHECK FOR BCM DTC B121A:11

    • Ignition ON.
    • Using a diagnostic scan tool, carry out the BCM self-test.

    Is DTC B121A:11 present? 

    Yes  GO to  P3.
    No  GO to  P5.

  3. P3 CHECK THE KEYLESS ENTRY KEYPAD FOR A SHORT TO GROUND

    • Ignition OFF.
    • Disconnect: Keyless Entry Keypad C500 .
    • Ignition ON.
    • Using a diagnostic scan tool, clear the BCM DTCs.
    • Using a diagnostic scan tool, carry out the BCM self-test.

    Is DTC B121A:11 still present? 

    Yes  GO to  P4.
    No  INSTALL a new keyless entry keypad. REFER to Keyless Entry Keypad .

  4. P4 CHECK THE KEYPAD ILLUMINATION OUTPUT CIRCUIT FOR A SHORT TO GROUND

    • Ignition OFF.
    • Measure:
      Positive Lead Measurement / Action Negative Lead
      C500-2
      GFD29916Courtesy of FORD MOTOR COMPANY
      		 Ground

    Is the resistance greater than 10, 000 ohms? 

    Yes  GO to  P8.
    No  REPAIR the circuit.
    5. NOTE: This step checks for a voltage increase when the keypad lamp is commanded on.
    NOTE: The BCM sends out a constant reference voltage on the keypad illumination circuit for its own circuit diagnostics. This voltage is approximately 10 volts +/- 1 volt.

  5. P5 CHECK THE BCM OUTPUT USING THE KEYPAD LAMP OUTPUT STATUS (KEY_PAD_LMP) PID
    • Ignition OFF.
    • Disconnect: Keyless Entry Keypad C500 .
    • Ignition ON.
    • Measure and record:
      Positive Lead Measurement / Action Negative Lead
      C500-2
      GFD29915Courtesy of FORD MOTOR COMPANY
      		 Ground
    • Using a diagnostic scan tool, command the BCM KEY_PAD_LMP PID on.
    • Measure and record:
      Positive Lead Measurement / Action Negative Lead
      C500-2
      GFD29915Courtesy of FORD MOTOR COMPANY
      		 Ground
    • Using a diagnostic scan tool, command the BCM KEY_PAD_LMP PID off.

    Does the voltage increase approximately 1 volt when the PID is commanded on? 

    Yes  GO to  P6.
    No  GO to  P7.

  6. P6 CHECK THE KEYPAD ILLUMINATION GROUND CIRCUIT FOR AN OPEN

    • Ignition OFF.
    • Measure:
      Positive Lead Measurement / Action Negative Lead
      C500-4
      GFD29916Courtesy of FORD MOTOR COMPANY
      		 Ground

    Is the resistance less than 3 ohms? 

    Yes  INSTALL a new keyless entry keypad. REFER to Keyless Entry Keypad .
    No  REPAIR the circuit.

  7. P7 CHECK THE BCM KEYPAD ILLUMINATION OUTPUT CIRCUIT FOR AN OPEN

    • Ignition OFF.
    • Measure:
      Positive Lead Measurement / Action Negative Lead
      C500-2
      GFD29916Courtesy of FORD MOTOR COMPANY
      		 C2280C-26

    Is the resistance less than 3 ohms? 

    Yes  GO to  P8.
    No  REPAIR the circuit.

  8. P8 CHECK FOR CORRECT BCM OPERATION

    • Disconnect and inspect all the BCM connectors.
    • Repair:
      • corrosion (install new connector or terminals - clean module pins)
      • damaged or bent pins - install new terminals/pins
      • pushed-out pins - install new pins as necessary
    • Reconnect the BCM connectors. Make sure they seat and latch correctly.
    • Operate the system and determine if the concern is still present.

    Is the concern still present? 

    Yes  CHECK On-Line Automotive Service Information System (OASIS) for any applicable TSBs. If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no TSBs address this concern, Refer to BCM Hardware Testing .
    No  The system is operating correctly at this time. The concern may have been caused by module connections. ADDRESS the root cause of any connector or pin issues.
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