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Pinpoint Test N: U3003

  1. Refer to ELECTRONIC ENGINE CONTROLS - 2.3L for schematic and connector information.

    Normal Operation and Fault Conditions 

    The PCM receives voltage at all times from the BJB.

    DTC Fault Trigger Conditions 

    DTC Description Fault Trigger Condition
    PCM U3003:00 Battery Voltage: No Sub Type Information This DTC sets when the PCM detects lower than expected battery voltage on the voltage supply input circuit.

    Possible Sources 

    • Wiring, terminals or connectors
    • Charging system concern
    • Battery concern
    • BJB
    • PCM

  2. N1 RECHECK THE BCM (BODY CONTROL MODULE) DIAGNOSTIC TROUBLE CODES (DTCS)

    • Ignition ON.

    • Using a diagnostic scan tool, clear the Diagnostic Trouble Codes (DTCs).

    • Wait 10 seconds.

    • Using a diagnostic scan tool, perform the BCM self-test.

    Is DTC U3003 still present? 

    Yes  GO to  N2
    No  The system is operating correctly at this time. The DTC may have been set due to a previous low battery voltage condition. CLEAR the DTC.

  3. N2 CHECK FOR CHARGING SYSTEM DIAGNOSTIC TROUBLE CODES (DTCS) SET IN OTHER MODULES

    • Using a diagnostic scan tool, retrieve all Diagnostic Trouble Codes (DTCs).

    Are any charging system Diagnostic Trouble Codes (DTCs) recorded? 

    Yes  DIAGNOSE the charging system concern. REFER to: Charging System - 2.3L EcoBoost (199kW/270PS) .
    No  GO to  N3

  4. N3 CHECK THE BATTERY CONDITION AND STATE OF CHARGE

    • Check the battery condition and verify the battery is fully charged. REFER to: Battery .

    Is the battery OK and fully charged? 

    Yes  GO to  N4
    No  If the battery is discharged, DIAGNOSE the cause of the low battery condition. REFER to: Charging System - 2.3L EcoBoost (199kW/270PS) . If the battery condition fails, INSTALL a new battery. REFER to: Battery .

  5. N4 COMPARE THE PCM (POWERTRAIN CONTROL MODULE) BATT_V_INF (V) PID (PARAMETER IDENTIFICATION) WITH THE ACTUAL BATTERY VOLTAGE

    • Start the engine.

    • Turn on accessories (climate control blower on high speed, exterior lights).

    • With the engine running at idle, measure and record battery voltage:
      Positive Lead Measurement / Action Negative Lead
      GFD625750Courtesy of FORD MOTOR COMPANY
      GFD623860Courtesy of FORD MOTOR COMPANY
      GFD625751Courtesy of FORD MOTOR COMPANY

    • Access the PCM and monitor the BATT_V_INF (V) PID

    Is the recorded battery voltage within 0.2 volt of the PID? 

    Yes  TURN the engine off, GO to  N5
    No  GO to  N5

  6. N5 CHECK THE PCM (POWERTRAIN CONTROL MODULE) VOLTAGE SUPPLY CIRCUITS

    • Ignition OFF.

    • Disconnect PCM C1551B.

    • Connect a fused jumper.
      Positive Lead Measurement / Action Negative Lead
      C175B-84
      GFD623862Courtesy of FORD MOTOR COMPANY
      		 Ground

    • Ignition ON.

    • Measure:
      Positive Lead Measurement / Action Negative Lead
      C175B-1
      GFD623860Courtesy of FORD MOTOR COMPANY
      		 Ground
      C175B-2
      GFD623860Courtesy of FORD MOTOR COMPANY
      		 Ground
      C175B-3
      GFD623860Courtesy of FORD MOTOR COMPANY
      		 Ground

    Are the voltages within 0.2 volt of the recorded battery voltage? 

    Yes  GO to  N6
    No  REPAIR the circuit in question for high resistance.

  7. N6 CHECK THE PCM (POWERTRAIN CONTROL MODULE) GROUNDS

    • Ignition OFF.

    • Removed the fused jumper.

    • Measure:
      Positive Lead Measurement / Action Negative Lead
      C175B-43
      GFD623861Courtesy of FORD MOTOR COMPANY
      		 Ground
      C175B-64
      GFD623861Courtesy of FORD MOTOR COMPANY
      		 Ground
      C175B-65
      GFD623861Courtesy of FORD MOTOR COMPANY
      		 Ground
      C175B-66
      GFD623861Courtesy of FORD MOTOR COMPANY
      		 Ground

    Are the resistances less than 3 ohms? 

    Yes  GO to  N7
    No  REPAIR the circuit in question for high resistance.

  8. N7 CHECK FOR CORRECT PCM (POWERTRAIN CONTROL MODULE) OPERATION

    • Disconnect and inspect the PCM and all related in-line 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 all PCM and all related in-line 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 OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, follow TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, Refer to PCM GUIDED ROUTINE 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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