LEMON Manuals: Even more car manuals for everyone
Home >> Acura >> 2011 >> RDX 2.3 TB2 >> Repair and Diagnosis >> Engine Performance >> System >> PGM-FI System >> DLC Circuit Troubleshooting

DLC Circuit Troubleshooting

NOTE: If you suspect the HDS or the HDS DLC cable may be the source of the communication problem, verify that they are working properly by connecting them to a known-good, like vehicle and system, and checking for communication problems.
  1. Turn the ignition switch to LOCK (0).
  2. Connect the HDS to the DLC (see GENERAL TROUBLESHOOTING INFORMATION ).
  3. Turn the ignition switch to ON (II), and read the HDS.

    Does the HDS identify the vehicle? 

    YES  -Go to step 4.

    NO  -Go to step  23.

  4. Check for Pending or Confirmed DTCs in the PGM-FI system with the HDS.

    Are any Pending or Confirmed DTCs indicated? 

    YES  -Go to the indicated DTCS TROUBLESHOOTING .

    NO  -

    • If the HDS does not communicate with the SRS, go to step 5.
    • If the HDS does not communicate with the VSA system, go to step  7.
    • If the HDS does not communicate with the SH-AWD system, go to step  9.
    • If the HDS does not communicate with the TPMS system, go to step  11.
    • If the HDS does not communicate with the IMMOBI (immobilizer) system, go to step  13.
    • If the HDS does not communicate with the BODY ELECTRICAL system, go to step  15.
  5. Turn the ignition switch to LOCK (0).
  6. Turn the ignition switch to ON (II), and watch the SRS indicator.

    Does the SRS indicator come on and go off? 

    YES  -Go to step 7.

    NO  -Go to the SRS general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION ).

  7. Turn the ignition switch to LOCK (0).
  8. Turn the ignition switch to ON (II), and watch the VSA indicator.

    Does the VSA indicator come on and go off? 

    YES  -Go to step 9.

    NO  -Go to the VSA symptom troubleshooting for ABS indicator, brake system indicator, VSA indicator do not go off (see ABS INDICATOR, BRAKE SYSTEM INDICATOR, AND VSA INDICATOR DO NOT GO OFF ).

  9. Turn the ignition switch to LOCK (0).
  10. Turn the ignition switch to ON (II), and watch the SH-AWD indicator.

    Does the SH-AWD indicator come on and go off? 

    YES  -Go to step 11.

    NO  -Go to the SH-AWD symptom troubleshooting for SH-AWD indicator does not go off, and no DTCs are stored (see DTC 91-1: SH-AWD CONTROL UNIT PROGRAMMING ERROR ).

  11. Turn the ignition switch to LOCK (0).
  12. Turn the ignition switch to ON (II), and watch the TPMS indicator.

    Does the TPMS indicator come on and go off? 

    YES  -Go to step 13.

    NO  -Go to the TPMS symptom troubleshooting for TPMS indicator does not go off, and no DTCs are stored (see TPMS INDICATOR DOES NOT COME ON, AND NO DTCS ARE STORED ).

  13. Turn the ignition switch to LOCK (0).
  14. Turn the ignition switch to ON (II), and watch the immobilizer indicator.

    Does the immobilizer indicator stay on or flash? 

    YES  -Troubleshoot the immobilizer system (see SYMPTOM TROUBLESHOOTING INFORMATION ).

    NO  -Go to step 15.

  15. Do the gauge self-diagnostic function (see SELF-DIAGNOSTIC FUNCTION ).
  16. Check for B-CAN system DTCs without the HDS (see GENERAL TROUBLESHOOTING INFORMATION ).

    Are any B-CAN DTCs indicated? 

    YES  -Go to the indicated DTCS TROUBLESHOOTING .

    NO  -Go to step 17.

  17. Turn the ignition switch to LOCK (0), then do the battery terminal disconnecting procedure (see USING THE GR8 BATTERY DIAGNOSTIC STATION ), and wait at least 3 minutes before starting work.
  18. Disconnect the HDS from the DLC.
  19. Check for continuity between DLC terminal No. 7 and body ground.
    Fig 1: Checking Continuity Between DLC Terminal No. 7 And Body Ground
    G08059453Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 20.

    NO  -Go to step  21.

  20. Continue to check for continuity between DLC terminal No. 7 and body ground, while disconnecting these connectors, one at a time:
    • SRS unit connector A (28P)
    • VSA modulator-control unit 46P connector
    • SH-AWD control unit connector A (20P) (With SH-AWD)
    • TPMS control unit 20P connector
    • Immobilizer-keyless control unit 7P connector
    • Audio unit 17P connector
    • Under-dash fuse/relay box connector Q(16P)

    Does continuity go away when one of the above parts is disconnected? 

    YES  -Replace the part that caused an open when it was disconnected.

    NO  -Repair a short in the wire between the DLC (K-line) and the VSA modulator-control unit, the SRS unit, the SH-AWD control unit (With SH-AWD), the TPMS control unit, the immobilizer-keyless control unit, the audio unit, or the under-dash fuse/relay box.

  21. Connect DLC terminal No. 7 to body ground with a jumper wire.
    Fig 2: Connecting DLC Terminal No. 7 To Body Ground Using Jumper Wire
    G08059454Courtesy of AMERICAN HONDA MOTOR CO., INC.
  22. Check for continuity between body ground and the following connector terminals, with all listed control units disconnected.
    Connector Terminal
    SRS unit A (28P) No. 24 (LT BLU)
    VSA modulator-control unit (46P) No. 15 (LT BLU)
    SH-AWD control unit A (20P) (With SH-AWD) No. 5 (LT BLU)
    TPMS control unit (20P) No. 7 (LT BLU)
    Immobilizer-keyless control unit (7P) No. 5 (LT BLU)
    Audio unit A (17P) No. 6 (LT BLU)
    Under-dash fuse/relay box (Q) (16P) No. 8 (LT BLU)

    Is there continuity between the DLC terminal and each of the terminals in the chart? 

    YES  -Replace the unit that cannot communicate with the HDS.

    NO  -Repair an open in the wire between the DLC (K-line) and the appropriate connector.

  23. Check for B-CAN system DTCs without the HDS (see GENERAL TROUBLESHOOTING INFORMATION ).

    Is DTC B1168, B1169, and/or B1178 indicated? 

    YES  -Go to step  34.

    NO  -Go to step 24.

  24. Turn the ignition switch to LOCK (0).
  25. Disconnect the HDS from the DLC.
  26. Measure the voltage between DLC terminal No. 16 and body ground.
    Fig 3: Measuring Voltage Between DLC Terminal No. 16 And Body Ground
    G08059455Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step 27.

    NO  -Repair an open in the wire between DLC terminal No. 16 and the No. 19 Fl MAIN (15 A) fuse in the under-hood fuse/relay box.

  27. Measure the voltage between DLC terminals No. 4 and No. 16.
    Fig 4: Measuring Voltage Between DLC Terminals No. 4 And No. 16
    G08059456Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step 28.

    NO  -Repair an open in the wire between DLC terminal No. 4 and G501 (see CONNECTOR TO HARNESS INDEX ).

  28. Connect the HDS to the DLC (see GENERAL TROUBLESHOOTING INFORMATION ).
  29. Jump the SCS line with the HDS.
  30. Disconnect PCM connector A (44P).
  31. Disconnect the HDS from the DLC.
  32. Check for continuity between PCM connector terminal A36 and DLC terminal No. 6.
    Fig 5: Checking Continuity Between PCM Connector Terminal A36 And DLC Terminal No. 6
    G08059457Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 33.

    NO  -Repair an open in the wire between the PCM (A36) and DLC terminal No. 6.

  33. Check for continuity between PCM connector terminal A37 and DLC terminal No. 14.
    Fig 6: Checking Continuity Between PCM Connector Terminal A37 And DLC Terminal No. 14
    G08059458Courtesy 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 ), then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM (see PCM REPLACEMENT  ).

    NO  -Repair an open in the wire between the PCM (A37) and DLC terminal No. 14.

  34. Try to start the engine.

    Does the engine start and idle? 

    YES  -Go to the F-CAN circuit troubleshooting (see F-CAN CIRCUIT TROUBLESHOOTING  ).

    NO  -

    • If the starter cranks, turn the ignition switch to LOCK (0), and go to step  37.
    • If the starter does not crank, go to step 35.
  35. Turn the ignition switch to LOCK (0).
  36. Check the No. 2 IG MAIN (50 A) fuse in the under-hood fuse/relay box.

    Is the fuse OK? 

    YES  -Repair an open in the wire between the No. 2 IG MAIN (50 A) fuse and the ignition switch. If the wire is OK, go to step 37.

    NO  -Replace the under-hood fuse/relay box (see REMOVAL AND INSTALLATION ). Also replace the No. 2 IG MAIN (50 A) fuse.

  37. Inspect the No. 19 Fl MAIN (15 A) fuse in the under-hood fuse/relay box.

    Is the fuse OK? 

    YES  -Go to step  44.

    NO  -Go to step 38.

  38. Remove the blown No. 19 Fl MAIN (15 A) fuse from the under-hood fuse/relay box.
  39. Remove PGM-FI main relay 1 (A) from the under-hood fuse/relay box.
    Fig 7: Identifying PGM-FI Relay 1
    G08059459Courtesy of AMERICAN HONDA MOTOR CO., INC.
  40. Check for continuity between body ground and PGM-FI main relay 1 4P connector terminals No. 1 and No. 3 individually.
    Fig 8: Checking Continuity Between Body Ground And PGM-FI Main Relay 1 4P Connector Terminals No. 1
    G08059460Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Replace the under-hood fuse/relay box (see REMOVAL AND INSTALLATION ). Also replace the No. 19 Fl MAIN (15 A) fuse.

    NO  -Go to step 41.

  41. While disconnecting each of the parts or connectors below, one at a time, check for continuity between PGM-FI main relay 1 4P connector terminal No. 2 and body ground.
    • PGM-FI main relay 2
    • PCM connector A (44P)
    • Each injector 2P connector
    • Camshaft position (CMP) sensor B 3P connector
    • Crankshaft position (CKP) sensor 3P connector
    • Electronic throttle control system (ETCS) control relay
      Fig 9: Checking Continuity Between PGM-FI Main Relay 1 4P Connector Terminal No. 2 And Body Ground
      G08059461Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Does continuity go away when one of the above parts is disconnected? 

    YES  -Replace the part that made the short to body ground go away when disconnected. If the part is the PCM, update the PCM if it does not have the latest software (see PCM UPDATE  ), or substitute a known-good PCM (see SUBSTITUTING THE PCM ), then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM (see PCM REPLACEMENT  ). Also replace the No. 19 Fl MAIN (15 A) fuse.

    NO  -Go to step 42.

  42. Disconnect these parts or connectors:
    • PGM-FI main relay 2
    • PCM connector A (44P)
    • Injectors
    • Camshaft position (CMP) sensor B
    • Crankshaft position (CKP) sensor
    • Electronic throttle control system (ETCS) control relay
  43. Check for continuity between PGM-FI main relay 1 4P connector terminal No. 2 and body ground.
    Fig 10: Checking Continuity Between PGM-FI Main Relay 1 4P Connector Terminal No. 2 And Body Ground
    G08059462Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair a short in the wire between PGM-FI main relay 1 and each part. Also replace the No. 19 Fl MAIN (15 A) fuse.

    NO  -Replace PGM-FI main relay 1. Also replace the No. 19 Fl MAIN (15 A) fuse.

  44. Inspect the No. 2 FUEL PUMP (20 A) fuse in the under-dash fuse/relay box.

    Is the fuse OK? 

    YES  -Go to step  51.

    NO  -Go to step 45.

  45. Remove the blown No. 2 FUEL PUMP (20 A) fuse from the under-dash fuse/relay box.
  46. Jump the SCS line with the HDS.
  47. Disconnect PCM connector C (44P).
  48. Check for continuity between PCM connector terminal C36 and body ground.
    Fig 11: Checking Continuity Between PCM Connector Terminal C36 And Body Ground
    G08059463Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 49.

    NO  -Replace the No. 2 FUEL PUMP (20 A) fuse, and update the PCM if it does not have the latest software (see PCM UPDATE  ), or substitute a known-good PCM (see SUBSTITUTING THE PCM ), then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM (see PCM REPLACEMENT  ).

  49. Remove the driver's dashboard undercover (see CENTER PANEL REMOVAL/INSTALLATION ), then remove PGM-FI main relay 2 (A) from the under-dash fuse/relay box.
    Fig 12: Identifying PGM-FI Main Relay 2
    G08059464Courtesy of AMERICAN HONDA MOTOR CO., INC.
  50. Check for continuity between PCM connector terminal C36 and body ground.
    Fig 13: Checking Continuity Between PCM Connector Terminal C36 And Body Ground
    G08059465Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair a short in the wire between the No. 2 FUEL PUMP (20 A) fuse and the PCM (C36), between the No. 2 FUEL PUMP (20 A) fuse and PGM-FI main relay 2, or between the No. 2 FUEL PUMP (20 A) fuse and the immobilizer-keyless control unit. Also replace the No. 2 FUEL PUMP (20 A) fuse.

    NO  -Go to step 51.

  51. Jump the SCS line with the HDS.
  52. Disconnect PCM connectors A (44P) and C (44P) (if not disconnected).
  53. Turn the ignition switch to ON (II).
  54. Measure the voltage between PCM connector terminal C36 and body ground.
    Fig 14: Measuring Voltage Between PCM Connector Terminal C36 And Body Ground
    G08059466Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step 55.

    NO  -Repair an open in the wire between the No. 2 FUEL PUMP (20 A) fuse and the PCM (C36).

  55. Measure the voltage between PCM connector terminal A6 and body ground.
    Fig 15: Measuring Voltage Between PCM Connector Terminal A6 And Body Ground
    G08059467Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step  60.

    NO  -Go to step 56.

  56. Turn the ignition switch to LOCK (0).
  57. Remove PGM-FI main relay 1 (A) from the under-hood fuse/relay box.
    Fig 16: Identifying PGM-FI Main Relay 1
    G08059468Courtesy of AMERICAN HONDA MOTOR CO., INC.
  58. Measure the voltage between PGM-FI main relay 1 4P connector terminal No. 3 and body ground.
    Fig 17: Measuring Voltage Between PGM-FI Main Relay 1 4P Connector Terminal No. 3 And Body Ground
    G08059469Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step 59.

    NO  -Replace the under-hood fuse/relay box (see REMOVAL AND INSTALLATION ).

  59. Check for continuity between PCM connector terminal A6 and PGM-FI main relay 1 4P connector terminal No. 4.
    Fig 18: Checking Continuity Between PCM Connector Terminal A6 And PGM-FI Main Relay 1 4P Connector Terminal No. 4
    G08059470Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Test PGM-FI main relay 1 (see POWER RELAY TEST ). If the relay is OK, update the PCM if it does not have the latest software (see PCM UPDATE  ), or substitute a known-good PCM (see SUBSTITUTING THE PCM ), then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM (see PCM REPLACEMENT  ).

    NO  -Repair an open in the wire between the PCM (A6) and PGM-FI main relay 1.

  60. Turn the ignition switch to LOCK (0).
  61. Remove PGM-FI main relay 1 (A) from the under-hood fuse/relay box.
    Fig 19: Identifying PGM-FI Main Relay 1
    G08059471Courtesy of AMERICAN HONDA MOTOR CO., INC.
  62. Measure the voltage between PGM-FI main relay 1 4P connector terminal No. 1 and body ground.
    Fig 20: Measuring Voltage Between PGM-FI Main Relay 1 4P Connector Terminal No. 1 And Body Ground
    G08059472Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step 63.

    NO  -Replace the under-hood fuse/relay box (see REMOVAL AND INSTALLATION ).

  63. Check for continuity between PCM connector terminal A8 and PGM-FI main relay 1 4P connector terminal No. 2.
    Fig 21: Checking Continuity Between PCM Connector Terminal A8 And PGM-FI Main Relay 1 4P Connector Terminal No. 2
    G08059473Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 64.

    NO  -Repair an open in the wire between the PCM (A8) and PGM-FI main relay 1.

  64. Test PGM-FI main relay 1 (see POWER RELAY TEST ).

    Is PGM-FI main relay 1 OK? 

    YES  -Go to step 65.

    NO  -Replace PGM-FI main relay 1.

  65. Jump the SCS line with the HDS.
  66. Disconnect PCM connector B (44P).
  67. Check for continuity between body ground and PCM connector terminals B1, B36, C2, C40, and C44 individually.
    Fig 22: Checking Continuity Between Body Ground And PCM Connector Terminals B1
    G08059474Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 68.

    NO  -Repair an open in the wire between the PCM (B1, B36, C2, C40, C44) and G101 (see CONNECTOR TO FUSE/RELAY BOX INDEX ).

  68. Check for continuity between PCM connector terminal C13 and body ground.
    Fig 23: Checking Continuity Between PCM Connector Terminal C13 And Body Ground
    G08059475Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 69.

    NO  -Go to step  70.

  69. Continue to check for continuity between PCM connector terminal C13 and body ground, while disconnecting these connectors, one at a time:
    • MAP sensor 3P connector
    • Input shaft (mainshaft) speed sensor 3P connector
      Fig 24: Checking Continuity Between PCM Connector Terminal C13 And Body Ground
      G08059476Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Does continuity go away when one of the above parts is disconnected? 

    YES  -Replace the part that caused an open when it was disconnected.

    NO  -Repair a short in the wire between the PCM (C13) and the MAP sensor or the input shaft (mainshaft) speed sensor.

  70. Check for continuity between PCM connector terminal B18 and body ground.
    Fig 25: Checking Continuity Between PCM Connector Terminal B18 And Body Ground
    G08059477Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 71.

    NO  -Go to step  72.

  71. Continue to check for continuity between PCM connector terminal B18 and body ground, while disconnecting these connectors, one at a time:
    • Turbocharger boost sensor 3P connector
    • Output shaft (countershaft) speed sensor 3P connector
      Fig 26: Checking Continuity Between PCM Connector Terminal B18 And Body Ground
      G08059478Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Does continuity go away when one of the above parts is disconnected? 

    YES  -Replace the part that caused an open when it was disconnected.

    NO  -Repair a short in the wire between the PCM (B18) and the turbocharger boost sensor or the output shaft (countershaft) speed sensor.

  72. Check for continuity between PCM connector terminal C12 and body ground.
    Fig 27: Checking Continuity Between PCM Connector Terminal C12 And Body Ground
    G08059479Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 73.

    NO  -Go to step  74.

  73. Continue to check for continuity between PCM connector terminal C12 and body ground, while disconnecting the throttle body 6P connector.
    Fig 28: Checking Continuity Between PCM Connector Terminal C12 And Body Ground
    G08059480Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair a short in the wire between the PCM (C12) and the throttle body.

    NO  -Replace the throttle body (see THROTTLE BODY REMOVAL/INSTALLATION ).

  74. Check for continuity between PCM connector terminal A25 and body ground.
    Fig 29: Checking Continuity Between PCM Connector Terminal A25 And Body Ground
    G08059481Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 75.

    NO  -Go to step  76.

  75. Continue to check for continuity between PCM connector terminal A25 and body ground, while disconnecting the APP sensor 6P connector.
    Fig 30: Checking Continuity Between PCM Connector Terminal A25 And Body Ground
    G08059482Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair a short in the wire between the PCM (A25) and APP sensor A.

    NO  -Replace the accelerator pedal module (see APP SENSOR SIGNAL INSPECTION ).

  76. Check for continuity between PCM connector terminal A24 and body ground.
    Fig 31: Checking Continuity Between PCM Connector Terminal A24 And Body Ground
    G08059483Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 77.

    NO  -Go to step  78.

  77. Continue to check for continuity between PCM connector terminal A24 and body ground, while disconnecting the APP sensor 6P connector.
    Fig 32: Checking Continuity Between PCM Connector Terminal A24 And Body Ground
    G08059484Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair a short in the wire between the PCM (A24) and APP sensor B.

    NO  -Replace the accelerator pedal module (see APP SENSOR SIGNAL INSPECTION ).

  78. Check for continuity between PCM connector terminal A19 and body ground.
    Fig 33: Checking Continuity Between PCM Connector Terminal A19 And Body Ground
    G08059485Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 79.

    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 ), then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM (see PCM REPLACEMENT  ).

  79. Continue to check for continuity between PCM connector terminal A19 and body ground, while disconnecting these connectors, one at a time:
    • A/C pressure sensor 3P connector
    • FTP sensor 3P connector
    • Brake booster pressure sensor 3P connector
      Fig 34: Checking Continuity Between PCM Connector Terminal A19 And Body Ground
      G08059486Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Does continuity go away when one of the above parts is disconnected? 

    YES  -Replace the part that caused an open when it was disconnected.

    NO  -Repair a short in the wire between the PCM (A19) and the A/C pressure sensor, the FTP sensor, or the brake booster pressure sensor.

scientia non olet · About LEMON Manuals