LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Ford >> 2021 >> F-150 Raptor >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Pinpoint Tests (Diesel) >> Pinpoint Tests AE: Unable To Activate Self Test/Network Communication Error >> Test Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Test Procedure

  1. AE1 CARRY OUT A VEHICLE INSPECTION AND VERIFY THE SELF-TEST PROCEDURE 
    NOTE: If the self-test or communication concern occurred after a failed or an aborted reprogram, the module may be blank. Attempt to reprogram the module again before continuing with this pinpoint test.
    • Visually inspect the following for obvious signs of damage:
      • harness circuits
      • electrical connections
    • Verify that the correct procedure was used to activate the self-test for the scan tool. Refer to SCAN TOOL SETUP AND FUNCTIONALITY .

    Was the correct self-test procedure used? 

    Yes No
    GO to  AE2. REFER to SCAN TOOL SETUP AND FUNCTIONALITY .
  2. AE2 CARRY OUT THE NETWORK TEST 
    NOTE: When using the scan tool, it 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 an IDS session cannot be established, IDS 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
    For DTC U0073, GO to  AE7.
    For DTCs U0101, U0402 and U1013, GO to  AE8.
    For DTC U0106, GO to  AE9.
    For DTC U0121, GO to  AE10.
    For DTCs U0140 or U0422, GO to  AE11.
    For DTC U0151, GO to  AE12.
    For DTC U0155, GO to  AE13.
    For DTC U0212, GO to  AE14.
    For DTCs U0307 and U0407, GO to  AE15.
    For DTC U0418, GO to  AE16.
    For DTCs U0102 and U041E, GO to  AE17.
    For DTC U0452, GO to  AE18.
    For DTC U010E, GO to  AE19.
    For DTC U0419, GO to  AE20.
    For all others, REFER to SYMPTOM CHARTS , GO to PINPOINT TEST QT , to continue diagnosis.    		 If only PCM indicates fail, GO to  AE3.
    For network test or all other modules indicate fail, REFER to the appropriate Module Communications Network article to diagnose the PCM does not respond to the scan tool symptom.
  3. AE3 CHECK THE VREF CIRCUIT FOR VOLTAGE 
    NOTE: PCM voltage and ground can be determined by measuring VREF voltage at a sensor.
    • For Transit Connect,
    • Ignition OFF.
    • MAP/CACT Sensor connector disconnected.
    • Ignition ON, engine OFF.
    • Measure the voltage between:
      (+) MAP/CACT Sensor Connector, Harness Side (-) MAP Sensor Connector, Harness Side
      VREF - Pin 2 SIGRTN - Pin 2
    • For all others,
    • Ignition OFF.
    • MAP Sensor connector disconnected.
    • Ignition ON, engine OFF.
    • Measure the voltage between:
      (+) MAP Sensor Connector, Harness Side (-) MAP Sensor Connector, Harness Side
      VREF - Pin 3 SIGRTN - Pin 2

    Is the voltage between 4.5 - 5.5 V? 

    Yes No
    REFER to the appropriate Module Communications Network article to diagnose the PCM does not respond to the scan tool symptom. GO to  AE4.
  4. AE4 CHECK THE ISP-R CIRCUIT FOR VOLTAGE 
    • Ignition OFF.
    • PCM-B connector disconnected.
    • Ignition ON, engine OFF.
    • Measure the voltage between:
      (+) PCM-B Connector, Harness Side (-)
      ISP-R Ground

    Is any voltage present? 

    Yes No
    GO to  AE5. REPAIR the open circuit. Clear the PCM DTCs.
    REPEAT the self-test.
  5. AE5 CHECK THE PCM VPWR CIRCUITS FOR VOLTAGE 
    • Ignition OFF.
    • Connect a 5 amp fused jumper wire between the following:
      Point A PCM-B Connector, Harness Side Point B
      PCMRC Ground
    • Ignition ON, engine OFF.
    • Measure the voltage between:
      (+) PCM-B Connector, Harness Side (-)
      VPWR Ground

    Is any voltage present? 

    Yes No
    GO to  AE6. GO to PINPOINT TEST AJ .
  6. AE6 CHECK THE PWRGND CIRCUITS FOR AN OPEN 
    • Ignition OFF.
    • Measure the resistance between:
      (+) PCM-B Connector, Harness Side (-)
      PWRGND Ground

    Are the resistances less than 5 ohms? 

    Yes No
    GO to  AE21. REPAIR the open circuit. Clear the PCM DTCs.
    REPEAT the self-test.
  7. AE7 CHECK FOR A CONTROL MODULE COMMUNICATION BUS A 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  AE21.
  8. AE8 CHECK FOR A TRANSMISSION CONTROL MODULE (TCM) CONCERN 
    • Check for any TCM DTCs.
    • Check for other TCM related symptoms.

    Is a concern present? 

    Yes No
    REFER to the appropriate Automatic Transaxle/Transmission, Diagnosis and Testing article. GO to  AE21.
  9. AE9 CHECK FOR A GLOW PLUG CONTROL MODULE (GPCM) CONCERN 
    • Check for any GPCM DTCs.
    • Check for other GPCM related symptoms.

    Is a concern present? 

    Yes No
    GO to PINPOINT TEST AF . GO to  AE21.
  10. AE10 CHECK FOR AN ANTI-LOCK BRAKE SYSTEM (ABS) MODULE CONCERN 
    • Check for any ABS module DTCs.
    • Check for other ABS module related symptoms.

    Is a concern present? 

    Yes No
    REFER to the appropriate Electronic Engine Controls, DTC Charts article. GO to  AE21.
  11. AE11 CHECK FOR A BODY CONTROL MODULE (BCM) CONCERN 
    • Check for any BCM DTCs.
    • Check for other BCM related symptoms.

    Is a concern present? 

    Yes No
    REFER to the appropriate Electronic Engine Controls, DTC Charts article. GO to  AE21.
  12. AE12 CHECK FOR A RESTRAINTS CONTROL MODULE (RCM) CONCERN 
    • Check for any RCM DTCs.
    • Check for other RCM related symptoms.

    Is a concern present? 

    Yes No
    REFER to the appropriate Electronic Engine Controls, DTC Charts article. GO to  AE21.
  13. AE13 CHECK FOR AN INSTRUMENT PANEL CLUSTER (IPC) CONTROL MODULE CONCERN 
    • Check for any IPC DTCs.
    • Check for other IPC control module related symptoms.

    Is a concern present? 

    Yes No
    REFER to the appropriate Electronic Engine Controls, DTC Charts article. GO to  AE21.
  14. AE14 CHECK FOR A STEERING COLUMN CONTROL MODULE (SCCM) CONCERN 
    • Check for any SCCM DTCs.
    • Check for other SCCM related symptoms.

    Is a concern present? 

    Yes No
    REFER to the appropriate Electronic Engine Controls, DTC Charts article. GO to  AE21.
  15. AE15 SOFTWARE INCOMPATIBILITY WITH GLOW PLUG CONTROL MODULE (GPCM) 
    • Check for any GPCM DTCs.
    • Check for other GPCM related symptoms.

    Is a concern present? 

    Yes No
    GO to PINPOINT TEST AF . GO to  AE21.
  16. AE16 INVALID DATA RECEIVED FROM ANTILOCK BRAKE SYSTEM (ABS) CONTROL MODULE 
    • Check for any ABS DTCs.
    • Check for other ABS related symptoms.

    Is a concern present? 

    Yes No
    REFER to the appropriate Vehicle Dynamic Systems, Inspection and Verification article to continue diagnosis. GO to  AE21.
  17. AE17 INVALID DATA RECEIVED FROM TRANSFER CASE CONTROL MODULE (TCCM) 
    • Check for any TCCM DTCs.
    • Check for other TCCM related symptoms.

    Is a concern present? 

    Yes No
    REFER to the appropriate Four Wheel Drive (4WD) Systems, Inspection and Verification article to continue diagnosis. GO to  AE21.
  18. AE18 INVALID DATA RECEIVED FROM RESTRAINTS CONTROL MODULE (RCM) 
    • Check for any RCM DTCs.
    • Check for other RCM related symptoms.

    Is a concern present? 

    Yes No
    REFER to the appropriate Supplemental Restraint System, Inspection and Verification article to continue diagnosis. GO to  AE21.
  19. AE19 CHECK FOR A REDUCTANT CONTROL MODULE CONCERN 
    • Check for any Reductant Control Module DTCs.
    • Check for other Reductant Control Module related symptoms.

    Is a concern present? 

    Yes No
    GO to PINPOINT TEST RM . GO to  AE21.
  20. AE20 CHECK FOR A STEERING EFFORT CONTROL MODULE CONCERN 
    • Check for any Steering Effort Control Module DTCs.
    • Check for any Steering Effort Control Module related symptoms.

    Is a concern present? 

    Yes No
    REFER to the appropriate Electronic Engine Controls, DTC Charts article. GO to  AE21.
  21. AE21 CHECK FOR CORRECT PCM OPERATION 
    • Disconnect all the PCM connectors.
    • Visually inspect for:
      • corrosion
      • pushed out pins
    • Connect all the PCM connectors and make sure they seat correctly.
    • Carry out the network test and verify the concern is still present.
    • Carry out the PCM self-test.
    • Verify the concern is still present.

    Is the concern still present? 

    Yes No
    INSTALL a new PCM. REFER to FLASH ELECTRICALLY ERASABLE PROGRAMMABLE READ ONLY MEMORY (EEPROM) . The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.
scientia non olet · About LEMON Manuals