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Shift Lock System Circuit Troubleshooting

NOTE: Check for A/T DTCs. If any DTCs are present, troubleshoot those first.
  1. Connect the HDS to the DLC.
    Fig 1: Identifying Data Link Connector
    G07362518Courtesy of AMERICAN HONDA MOTOR CO., INC.
  2. Turn the ignition switch to ON (II). Make sure the HDS communicates with the PCM. If it does not, go to the DLC circuit troubleshooting (see DLC CIRCUIT TROUBLESHOOTING ).
  3. Select Shift Lock Solenoid Test in the Miscellaneous Test Menu, and check that the shift lock solenoid operates with the HDS.

    Does the shift lock solenoid work properly? 

    YES  -Go to step  16.

    NO  -Go to step 4.

  4. Turn the ignition switch to LOCK (0).
  5. Remove the center console (see CENTER CONSOLE REMOVAL/INSTALLATION ).
  6. Disconnect the shift lock solenoid connector.
  7. Turn the ignition switch to ON (II).
  8. Measure the voltage between shift lock solenoid connector terminal No. 1 and body ground.
    Fig 2: Measuring Voltage Between Shift Lock Solenoid Connector Terminal No. 1 And Body Ground
    G07362519Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step 9.

    NO  -Check for a blown No. 21 (10 A) fuse in the driver's under-dash fuse/relay box. If the fuse is OK, repair an open in the wire between the shift lock solenoid connector terminal No. 1 and the driver's under-dash fuse/relay box.

  9. With the shift lever in P, press the brake pedal. Do not press the accelerator.
  10. Measure the voltage between shift lock solenoid connector terminals No. 1 and No. 2 while pressing the brake pedal.
    Fig 3: Measuring Voltage Between Shift Lock Solenoid Connector Terminals No. 1 And No. 2
    G07362520Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step 11.

    NO  -Go to step  12.

  11. Release the brake pedal, and measure the voltage between shift lock solenoid connector terminals No. 1 and No. 2. The shift lever must be in P.
    Fig 4: Measuring Voltage Between Shift Lock Solenoid Connector Terminals No. 1 And No. 2
    G07362521Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Repair a short to body ground in the wire between PCM connector terminal A2 and the shift lock solenoid connector.

    NO  -Check the shift lock mechanism. If the mechanism is OK, replace the shift lock solenoid (see SHIFT LOCK SOLENOID REPLACEMENT  ).

  12. Turn the ignition switch to LOCK (0).
  13. Jump the SCS line with the HDS.
  14. Disconnect PCM connector A (49P).
  15. Check for continuity between PCM connector terminal A2 and shift lock solenoid connector terminal No. 2.
    Fig 5: Checking Continuity Between PCM Connector Terminal A2 And Shift Lock Solenoid Connector Terminal No. 2
    G07362522Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Update the PCM if it does not have the latest software (see PCM UPDATE ), or substitute a known-good PCM (see SUBSTITUTING THE PCM ), and recheck. If the symptom goes away with a known-good PCM, replace the original PCM (see PCM REPLACEMENT ).

    NO  -Repair an open in the wire between PCM connector terminal A2 and the shift lock solenoid connector.

  16. Monitor the Brake Switch in the Data List with the HDS, and press the brake pedal.

    Is the Brake Switch ON? 

    YES  -Go to step  21.

    NO  -If the brake lights come on, go to step 17. If the brake lights do not work, repair faulty brake light circuit.

  17. Turn the ignition switch to LOCK (0).
  18. Jump the SCS line with the HDS.
  19. Disconnect PCM connector A (49P).
  20. Measure the voltage between PCM connector terminal A8 and body ground while pressing the brake pedal and when the brake pedal is released.
    Fig 6: Measuring Voltage Between PCM Connector Terminal A8 And Body Ground
    G07362523Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage while pressing the brake pedal and about 0 V when the pedal is released? 

    YES  -Update the PCM if it does not have the latest software (see PCM UPDATE ), or substitute a known-good PCM (see SUBSTITUTING THE PCM ), and recheck. If the symptom goes away with a known-good PCM, replace the original PCM (see PCM REPLACEMENT ).

    NO  -Repair an open in the wire between PCM connector terminal A8 and the brake pedal position switch.

  21. Monitor the A/T P Switch in the Data List with the HDS with the shift lever in P.

    Is the A/T P Switch ON? 

    YES  -Go to step  31.

    NO  -Go to step 22.

  22. Turn the ignition switch to LOCK (0).
  23. Disconnect the transmission range switch connector.
  24. Turn the ignition switch to ON (II).
  25. Connect a jumper wire between transmission range switch connector terminal No. 7 and body ground.
    Fig 7: Connecting Jumper Wire Between Transmission Range Switch Connector Terminal No. 7 And Body Ground
    G07362524Courtesy of AMERICAN HONDA MOTOR CO., INC.
  26. Check the A/T P switch signal with the HDS.

    Is the A/T P switch on? 

    YES  -Replace the transmission range switch.

    NO  -Go to step 27.

  27. Turn the ignition switch to LOCK (0).
  28. Jump the SCS line with the HDS.
  29. Disconnect PCM connector A (49P).
  30. Check for continuity between PCM connector terminal A16 and transmission range switch connector terminal No. 7.
    Fig 8: Checking Continuity Between PCM Connector Terminal A16 And Transmission Range Switch Connector Terminal No. 7
    G07362525Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Update the PCM if it does not have the latest software (see PCM UPDATE ), or substitute a known-good PCM (see SUBSTITUTING THE PCM ), and recheck. If the symptom goes away with a known-good PCM, replace the original PCM (see PCM REPLACEMENT ).

    NO  -Repair an open in the wire between PCM connector terminal A16 and the transmission range switch connector.

  31. Check APP Sensor A in the Data List with the HDS. Do not press the accelerator.

    Is the APP Sensor A opening 5 % or more, or the sensor A voltage 1.16 V or higher? 

    YES  -Check the APP sensor (see APP SENSOR SIGNAL INSPECTION ).

    NO  -Update the PCM if it does not have the latest software (see PCM UPDATE ), or substitute a known-good PCM (see SUBSTITUTING THE PCM ), and recheck. If the symptom goes away with a known-good PCM, replace the original PCM (see PCM REPLACEMENT ).