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Pinpoint Test AU: The Low Engine Oil Pressure RTT (RECONFIGURABLE Telltale) Is Never Or Always On (2.3L And 5.0L Non-Performance Engine)

  1. Refer to Instrument Cluster for schematic and connector information.

    Normal Operation and Fault Conditions 

    See Low Engine Oil Pressure RTT. REFER to: Message Center - System Operation and Component Description .

    If the engine rpm data or oil pressure warning indicator request message is missing less than 5 seconds, the IPC defaults the low engine oil pressure warning indicator to the last state (on or off), based upon the last message received.

    If the engine rpm data or oil pressure warning message is missing for 5 seconds or longer, the IPC defaults the low engine oil pressure warning indicator on.

    Possible Sources 

    • Wiring, terminals or connectors
    • Tachometer concern
    • Engine oil pressure switch
    • Base engine concern
    • GWM concern
    • PCM concern
    • IPC

  2. AU1 CHECK THE MESSAGE CENTER OPERATION

    • Ignition ON.

    • Close all doors, the hood and luggage compartment lid.

    • Clear all message center warnings by pressing the OK button for each warning present.

    • Monitor the door ajar RTT.

    • Open the driver door.

    • Clear the message center popup warning.

    • Monitor the door ajar RTT.

    Is the door ajar RTT off with the door closed, and on with the door open? 

    Yes  GO to  AU2
    No  GO to Pinpoint Test AO 

  3. AU2 PERFORM THE IPC (INSTRUMENT PANEL CLUSTER) SELF-TEST

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

    Are any Diagnostic Trouble Codes (DTCs) recorded? 

    Yes  REFER to DTC Chart: Instrument Panel Cluster (IPC) .
    No  GO to  AU3

  4. AU3 PERFORM THE PCM (POWERTRAIN CONTROL MODULE) SELF-TEST

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

    Are any Diagnostic Trouble Codes (DTCs) recorded? 

    Yes  REFER to: the appropriate Electronic Engine Controls article.
    No  GO to  AU4

  5. AU4 CHECK THE TACHOMETER OPERATION

    • Start the engine.

    • Verify the tachometer operates.

    Does the tachometer operate? 

    Yes  If the low engine oil pressure RTT is always on, GO to  AU5 If the low engine oil pressure RTT is never on, GO to  AU9
    No  GO to Pinpoint Test H 

  6. AU5 CHECK THE GWM (GATEWAY MODULE A) DIAGNOSTIC TROUBLE CODES (DTCS)

    • Using a diagnostic scan tool, check the GWM Continuous Memory Diagnostic Trouble Codes (CMDTCs).

    Are any Diagnostic Trouble Codes (DTCs) recorded? 

    Yes  REFER to: Communications Network
    No  GO to  AU6

  7. AU6 CHECK FOR A STUCK CLOSED ENGINE OIL PRESSURE SWITCH

    • Ignition OFF.

    • Disconnect Engine Oil Pressure Switch C103.

    • Ignition ON.

    • Observe the low engine oil pressure warning indicator.

    Does the low engine oil pressure warning indicator turn off? 

    Yes  INSTALL a new engine oil pressure switch. REFER to: Oil Pressure Switch
    No  GO to  AU7

  8. AU7 CHECK THE ENGINE OIL PRESSURE INPUT CIRCUIT FOR A SHORT TO GROUND AT THE PCM (POWERTRAIN CONTROL MODULE)

    • Ignition OFF.

    • Disconnect PCM C1551E (2.3L).

    • Disconnect PCM C175E (5.0L).

    • Measure:

      2.3L Engine 

      Positive Lead Measurement / Action Negative Lead
      C1551E-17
      GFD604413Courtesy of FORD MOTOR COMPANY
      		 Ground

      5.0L Engine 

      Positive Lead Measurement / Action Negative Lead
      C175E-69
      GFD604413Courtesy of FORD MOTOR COMPANY
      		 Ground

    Is the resistance greater than 10, 000 ohms? 

    Yes  GO to  AU8
    No  REPAIR the circuit.

  9. AU8 CHECK THE ENGINE OIL PRESSURE

    • Test the engine for low engine oil pressure.

    Was a low engine oil pressure concern detected? 

    Yes  REPAIR the low engine oil pressure concern. REFER to: Engine
    No  GO to  AU11

  10. AU9 CHECK FOR A STUCK OPEN ENGINE OIL PRESSURE SWITCH

    • Ignition OFF.

    • Disconnect Engine Oil Pressure Switch C103.

    • Connect a fused jumper wire:
      Lead 1 Measurement / Action Lead 2
      C103-1
      GFD604414Courtesy of FORD MOTOR COMPANY
      		 Ground

    • Start the engine.

    • Observe the low engine oil pressure warning indicator.

    Does the low engine oil pressure indicator turn on? 

    Yes  REMOVE the fused jumper wire. INSTALL a new engine oil pressure switch. REFER to: Oil Pressure Switch
    No  LEAVE the jumper wire connected. GO to  AU10

  11. AU10 CHECK THE ENGINE OIL PRESSURE INPUT CIRCUIT FOR AN OPEN AT THE PCM (POWERTRAIN CONTROL MODULE)

    • Ignition OFF.

    • Disconnect PCM C1551E (2.3L).

    • Disconnect PCM C175E (5.0L).

    • Measure:

      2.3L Engine 

      Positive Lead Measurement / Action Negative Lead
      C1551E-17
      GFD604413Courtesy of FORD MOTOR COMPANY
      		 Ground

      5.0L Engine 

      Positive Lead Measurement / Action Negative Lead
      C175E-69
      GFD604413Courtesy of FORD MOTOR COMPANY
      		 Ground

    Is the resistance less than 3 ohms? 

    Yes  REMOVE the fused jumper wire. GO to  AU11
    No  REMOVE the fused jumper wire. REPAIR the circuit.

  12. AU11 CHECK FOR CORRECT PCM (POWERTRAIN CONTROL MODULE) OPERATION

    • Ignition OFF.

    • Disconnect and inspect all PCM 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 PCM 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 service articles: TSB, GSB, SSM or FSA. If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern, Refer to PCM Guided Routine .
    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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