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Home >> Ford >> 2021 >> F-150 Raptor >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Pinpoint Tests (Diesel) >> Pinpoint Tests RM: Reductant Dosage Control Module >> Test Procedure
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Test Procedure

  1. RM1 PRELIMINARY DIAGNOSIS 

    Are DTCs P20EA, P20EB, P21CB, P21CC, U0073, U0100 or U0401 present? 

    Yes No
    For DTC U0073, GO to  RM2.
    For DTCs U0100 or U0401, GO to  RM3.
    For all others, GO to  RM5.    		 RETURN to SYMPTOM CHARTS for further direction.
  2. RM2 CHECK FOR A CONTROL MODULE COMMUNICATION BUS A OFF CONCERN 
    • Check for any other control module communication DTCs.
    • Check for other control module communication related symptoms.

    Is a concern present? 

    Yes No
    REFER to the appropriate Module Communications Network, Inspection and Verification article to continue diagnosis. GO to  RM14.
  3. RM3 CARRY OUT THE NETWORK TEST 
    NOTE: When using a scan tool, the scan tool attempts to communicate with the PCM first. After establishing communication with the PCM, the scan tool then attempts to communicate with all modules on the vehicle. If a session cannot be established, the scan tool may state no communication can be established with the PCM:
    • Choose No when the scan tool prompts whether or not to retry communication.
    • Enter a PCM part number, tear tag or calibration number to identify the vehicle and start a session. The PCM part number and 4-character tear tag are located on the PCM.
    • Ignition ON, engine OFF.
    • Carry out the network test.

    Do all modules indicate pass? 

    Yes No
    GO to  RM4. If only the reductant dosage control module indicates fail, GO to  RM5.
    For network test or all other modules indicates fail, REFER to the appropriate Module Communications Network, Communication Network Symptom Chart, to continue diagnosis.
  4. RM4 CHECK FOR A PCM CONCERN 
    • Check for any PCM DTCs.
    • Check for any other PCM related symptoms.

    Is a concern present? 

    Yes No
    DISREGARD the current diagnostic trouble code (DTC) at this time. DIAGNOSE the next DTC. GO to DIAGNOSTIC TROUBLE CODE (DTC) CHARTS AND DESCRIPTIONS . GO to  RM14.
  5. RM5 CHECK THE REDUCTANT DOSAGE CONTROL MODULE VPWR CIRCUITS FOR VOLTAGE 
    • Ignition OFF.
    • Reductant Dosage Control Module connector disconnected.
    • Connect a 5 amp fused jumper wire between the following:
      Point A Reductant Dosage Control Module Connector, Harness Side Point B
      RDCMRC - Pin 89 Ground
    • Ignition ON, engine OFF.
    • Measure the voltage between:
    (+) Reductant Dosage Control Module Connector, Harness Side (-)
    VPWR - Pin 1, 3, 5 Ground

    Is the voltage greater than 10.5 V? 

    Yes No
    GO to  RM6. GO to  RM7.
  6. RM6 CHECK THE REDUCTANT DOSAGE CONTROL MODULE GROUND CIRCUITS FOR AN OPEN 
    • Ignition OFF.
    • Measure the resistance between:
    (+) Reductant Dosage Control Module Connector, Harness Side (-)
    PWRGND Ground

    Is the resistance less than 5 ohms? 

    Yes No
    REFER to the appropriate Module Communications Network, Communication Network Symptom Chart, to continue diagnosis. REPAIR the open circuit.
    Clear the RDCM and PCM DTCs. REPEAT the self-test.
  7. RM7 CHECK THE REDUCTANT DOSAGE CONTROL MODULE RELAY 
    • Reductant Dosage Control Module Relay connector disconnected.
    • Carry out the reductant dosage control module relay component test. Refer to the appropriate Component Testing Wiring Diagrams.

    Is a concern present? 

    Yes No
    INSTALL a new Reductant Dosage Control Module relay.
    Clear the RDCM and PCM DTCs. REPEAT the self-test.    		 GO to  RM8.
  8. RM8 CHECK THE VOLTAGE TO THE REDUCTANT DOSAGE CONTROL MODULE RELAY 
    • Ignition ON, engine OFF.
    • Measure the voltage between:
    (+) Reductant Dosage Control Module Relay Connector, Harness Side (-)
    B+ - Pin 1, 3 Ground

    Is the voltage greater than 10.5 V? 

    Yes No
    GO to  RM9. REPAIR the open circuit.
    Clear the RDCM and PCM DTCs. REPEAT the self-test.
  9. RM9 CHECK THE RDCMRC CIRCUIT FOR AN OPEN 
    • Ignition OFF.
    • Measure the resistance between:
    (+) Reductant Dosage Control Module Relay Connector, Harness Side (-) Reductant Dosage Control Module Connector, Harness Side
    RDCMRC - Pin 2 RDCMRC - Pin 89

    Is the resistance less than 5 ohms? 

    Yes No
    GO to  RM10. REPAIR the open circuit.
    Clear the RDCM and PCM DTCs. REPEAT the self-test.
  10. RM10 CHECK THE RDCMRC CIRCUIT FOR A SHORT TO GROUND 
    • Measure the resistance between:
    (+) Reductant Dosage Control Module Relay Connector, Harness Side (-)
    RDCMRC - Pin 2 Ground

    Is the resistance greater than 10K ohms? 

    Yes No
    GO to  RM11. REPAIR the short circuit.
    Clear the RDCM and PCM DTCs. REPEAT the self-test.
  11. RM11 CHECK THE RDCMRC CIRCUIT FOR A SHORT TO VOLTAGE 
    • Ignition ON, engine OFF.
    • Measure the voltage between:
    (+) Reductant Dosage Control Module Relay Connector, Harness Side (-)
    RDCMRC - Pin 2 Ground

    Is any voltage present? 

    Yes No
    REPAIR the short circuit.
    Clear the RDCM and PCM DTCs. REPEAT the self-test.    		 GO to  RM12.
  12. RM12 CHECK THE REDUCTANT DOSAGE CONTROL MODULE VPWR CIRCUITS FOR AN OPEN 
    • Ignition OFF.
    • Measure the resistance between:
    (+) Reductant Dosage Control Module Relay Connector, Harness Side (-) Reductant Dosage Control Module Connector, Harness Side
    VPWR - Pin 5 VPWR - Pin 1, 3, 5

    Is the resistance less than 5 ohms? 

    Yes No
    GO to  RM13. REPAIR the open circuit.
    Clear the RDCM and PCM DTCs. REPEAT the self-test.
  13. RM13 CHECK THE REDUCTANT DOSAGE CONTROL MODULE VPWR CIRCUITS FOR A SHORT TO VOLTAGE 
    • Ignition ON, engine OFF.
    • Measure the voltage between:
    (+) Reductant Dosage Control Module Relay Connector, Component Side (-)
    VPWR - Pin 5 Ground

    Is any voltage present? 

    Yes No
    REPAIR the short circuit.
    Clear the RDCM and PCM DTCs. REPEAT the self-test.    		 GO to  RM14.
  14. RM14 CHECK FOR CORRECT REDUCTANT DOSAGE CONTROL MODULE OPERATION 
    • Disconnect the reductant dosage control module connector.
    • Visually inspect for:
      • pushed out pins
      • corrosion
    • Connect the reductant dosage control module connector and make sure it seats correctly.
    • Carry out the DCU self-test.
    • Verify the concern is still present.

    Is the concern still present? 

    Yes No
    For DTC U0100 or U0401, GO to PINPOINT TEST ZZ .
    For all others, INSTALL a new Reductant Dosage Control module. REFER to the appropriate Electronic Engine Controls article.    		 The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.
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