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2005-2006 models

  1. Connect the HDS (see HOW TO USE THE HDS (HONDA DIAGNOSTIC SYSTEM) ).
  2. Turn the ignition switch ON (II), and check the HDS.

    Does the HDS communicate with the ECM? 

    1. YES  - Go to step 3.
    2. NO  - Go to "DLC Circuit Troubleshooting" (see DLC CIRCUIT TROUBLESHOOTING ).
  3. Check for Temporary DTCs or DTCs with the HDS.

    Are any Temporary DTCs or DTCs indicated? 

    1. YES  - Go to the indicated DTC TROUBLESHOOTING 
    2. NO  - Go to step 4.
  4. Turn the ignition switch OFF.
  5. Turn the ignition switch ON (II) and watch the malfunction indicator lamp (MIL).

    Does the MIL come on and stay on for more than 20 seconds after turning the ignition switch ON (II)? 

    1. YES  - If the MIL always comes on and stays on, go to step  81. But if the MIL sometimes works normally, first check for these problems:
      • An intermittent short in the wire between the ECM (B17) and the data link connector (DLC).
      • An intermittent short in the wire between the ECM (A18) and the gauge assembly.
      • The readiness codes are not set (see HOW TO SET READINESS CODES ). (This is indicated if the MIL blinks five times after you turn the ignition switch ON (II) and wait about 20 seconds.)
    2. NO  - If the MIL is always off, go to step 6. But if the MIL sometimes works normally, first check for these problems:
      • A loose No. 6 (7.5 A) fuse in the under-dash fuse/relay box.
      • A loose No. 1 (50 A) fuse in the under-hood fuse/relay box.
      • A loose No. 7 (15 A) fuse in the under-hood fuse/relay box.
      • A loose No. 2 (15 A) fuse in the under-dash fuse/relay box.
      • A poor connection at ECM terminal A18.
      • An intermittent open in the GRN/ORN wire between the ECM (A18) and the gauge assembly.
      • An intermittent short in the wire between the ECM (C19) and the manifold absolute pressure (MAP) sensor.
      • An intermittent short in the wire between the ECM (C28) and the throttle position (TP) sensor, the brake booster pressure sensor, the fuel tank pressure (FTP) sensor, the exhaust gas recirculation (EGR) valve position sensor, or brake fluid pressure sensor A (M/T model).
      • An intermittent short in the wire between the ECM (C23) and brake fluid pressure sensor B (M/T model).
      • An intermittent short in the wire between the ECM (B6) and the TCM (CVT model).
  6. Turn the ignition switch OFF.
  7. Turn the ignition switch ON (II).

    Is the low oil pressure indicator on? 

    1. YES  - Go to step  10.
    2. NO  - Go to step 8.
  8. Inspect the No. 6 (7.5 A) fuse in the under-dash fuse/relay box.

    Is the fuse OK? 

    1. YES  - Go to step 9.
    2. NO  - Repair short in the wire between the No. 6 (7.5 A) fuse and the gauge assembly. Also replace the No. 6(7.5A) fuse.
  9. Inspect the No. 1 (50 A) fuse in the under-hood fuse/relay box.

    Is the fuse OK? 

    1. YES  - Repair open in the wire between the No. 1 (50 A) fuse and the gauge assembly. If the wires are OK, test the ignition switch (see TEST ).
    2. NO  - Repair short in the wire between the No. 1 (50 A) fuse and the under-dash fuse/relay box. Also replace the No. 1 (50 A) fuse.
  10. Try to start the engine.

    Does the engine start? 

    1. YES  - Go to step 11.
    2. NO  - Go to step  14.
  11. Turn the ignition switch OFF.
  12. Connect ECM connector terminal A18 to body ground with a jumper wire.
    Fig 1: Connecting ECM Connector Terminal A18 To Body Ground With Jumper Wire
    G03680917Courtesy of AMERICAN HONDA MOTOR CO., INC.
  13. Turn the ignition switch ON (II).

    Is the MIL on? 

    1. YES  - Update the ECM if it does not have the latest software, or substitute a known-good ECM (see ECM UPDATING AND SUBSTITUTION FOR TESTING-2002-2006 M/T MODELS AND CVT MODEL ), then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM (see ECM REPLACEMENT ).
    2. NO  - Check for an open in the wire between the ECM (A18) and the gauge assembly. Also check for a blown MIL bulb. If the wires and the bulb are OK, replace the gauge assembly.
  14. Turn the ignition switch OFF.
  15. Inspect the No. 7 (15 A) fuse in the under-hood fuse/relay box.

    Is the fuse OK? 

    1. YES  - Go to step  22.
    2. NO  - Go to step 16.
  16. Remove the blown No. 7 (15 A) fuse in the under-hood fuse/relay box.
  17. Remove the PGM-FI main relay (IGP).
  18. Check for continuity between body ground and PGM-FI main relay (IGP) 4P connector terminals No. 2 and No. 4 individually.
    Fig 2: Checking Continuity Between Body Ground And PGM-FI Main Relay (IGP) 4P Connector Terminals No. 2 And 4
    G03680918Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    1. YES  - Repair short in the wire between the No. 7 (15 A) fuse and the PGM-FI main relay (IGP). Also replace the No. 7 (15 A) fuse.
    2. NO  - Go to step 19.
  19. Disconnect the connectors from these components:
    • PGM-FI main relay (FUEL PUMP)
    • ECM connector B (25P)
    • Injectors
    • Idle air control (IAC) valve
  20. Check for continuity between PGM-FI main relay (IGP) 4P connector terminal No. 1 and body ground.
    Fig 3: Checking Continuity Between PGM-FI Main Relay (IGP) 4P Connector Terminal No. 1 And Body Ground
    G03680919Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    1. YES  - Repair short in YEL/BLK wire between the PGM-FI main relay (IGP) and each item. Also replace the No. 7 (15 A) fuse.
    2. NO  - Go to step 21.
  21. Reconnect each of the components of the connectors below, one at a time, and check for continuity between PGM-FI main relay (IGP) 4P connector terminal No. 1 and body ground.
    • PGM-FI main relay (FUEL PUMP)
    • ECM connector B (25P)
    • Each injector 2P connector
    • Idle air control (IAC) valve 3P connector
    Fig 4: Checking Continuity Between PGM-FI Main Relay (IGP) 4P Connector Terminal No. 1 And Body Ground
    G03680920Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    1. YES  - Replace the component that made continuity to body ground go away when disconnected. If the item is the ECM, update the ECM if it does not have the latest software, or substitute a known-good ECM (see ECM UPDATING AND SUBSTITUTION FOR TESTING-2002-2006 M/T MODELS AND CVT MODEL ), then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM (see ECM REPLACEMENT ). Also replace the No. 7 (15 A) fuse.
    2. NO  - Replace the PGM-FI main relay (IGP). Also replace the No. 7 (15 A) fuse.
  22. Inspect the No. 2 (15 A) fuse in the under-dash fuse/ relay box.

    Is the fuse OK? 

    1. YES  - Go to step  32.
    2. NO  - Go to step 23.
  23. Remove the blown No. 2 (15 A) fuse from the under-dash fuse/relay box.
  24. Remove ECM connector A (32P).
  25. Check for continuity between ECM connector terminal A26 and body ground.
    Fig 5: Checking Continuity Between ECM Connector Terminal A26 And Body Ground
    G03680921Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    1. YES  - Go to step 26.
    2. NO  - Replace the No. 2 (15 A) fuse, and update the ECM if it does not have the latest software, or substitute a known-good ECM (see ECM UPDATING AND SUBSTITUTION FOR TESTING-2002-2006 M/T MODELS AND CVT MODEL ), then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM (see ECM REPLACEMENT ).
  26. Remove the PGM-FI main relay (FUEL PUMP).
  27. Check for continuity between ECM connector terminal A26 and body ground.
    Fig 6: Checking Continuity Between ECM Connector Terminal A26 And Body Ground
    G03680922Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    1. YES  - Repair short in the wire between the No. 2 (15 A) fuse and the ECM (A26), or the No. 2 (15 A) fuse and the PGM-FI main relay (FUEL PUMP). Also replace the No. 2 (15 A) fuse.
    2. NO  - Go to step 28.
  28. Remove the fuel tank; 2005 model (see 2000-2005 MODELS ), 2006 model (see 2006 MODEL ).
  29. Check for continuity between fuel pump 5P connector terminal No. 5 and body ground.
    Fig 7: Checking Continuity Between Fuel Pump 5P Connector Terminal No. 5 And Body Ground
    G03680923Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    1. YES  - Repair short in the wire between the fuel pump and the PGM-FI main relay (FUEL PUMP). Also replace the No. 2 (15 A) fuse.
    2. NO  - Go to step 30.
  30. Reinstall the PGM-FI main relay (FUEL PUMP).
  31. Check for continuity between fuel pump 5P connector terminal No. 5 and body ground.
    Fig 8: Checking Continuity Between Fuel Pump 5P Connector Terminal No. 5 And Body Ground
    G03680924Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    1. YES  - Replace the PGM-FI main relay (FUEL PUMP). Also replace the No. 2 (15 A) fuse.
    2. NO  - Check the fuel pump, and replace it if necessary. Also replace the No. 2 (15 A) fuse.
  32. Turn the ignition switch ON (II).
  33. Measure voltage between ECM connector terminal A26 and body ground.
    Fig 9: Measuring Voltage Between ECM Connector Terminal A26 And Body Ground
    G03680925Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    1. YES  - Go to step 34.
    2. NO  - Repair open in the wire between the No. 2 (15 A) fuse and the ECM (A26).
  34. Turn the ignition switch OFF.
  35. Measure voltage between ECM connector terminal A8 and body ground.
    Fig 10: Measuring Voltage Between ECM Connector Terminal A8 And Body Ground
    G03680926Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    1. YES  - Go to step  41.
    2. NO  - Go to step 36.
  36. Remove the PGM-FI main relay (IGP).
  37. Measure voltage between PGM-FI main relay (IGP) 4P connector terminal No. 4 and body ground.
    Fig 11: Measuring Voltage Between PGM-FI Main Relay Connector Terminal No. 4 And Body Ground
    G03680927Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    1. YES  - Go to step 38.
    2. NO  - Repair open in the wire between the No. 7 (15 A) fuse and the PGM-FI main relay (IGP).
  38. Disconnect ECM connector A (32P).
  39. Connect ECM connector A8 to body ground with a jumper wire.
    Fig 12: Connecting ECM Connector A8 To Body Ground With Jumper Wire
    G03680928Courtesy of AMERICAN HONDA MOTOR CO., INC.
  40. Check for continuity between body ground and PGM-FI main relay (IGP) 4P connector terminal No. 3.
    Fig 13: Checking Continuity Between Body Ground And PGM-FI Main Relay (IGP) 4P Connector Terminal No. 3
    G03680929Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    1. YES  - Replace the PGM-FI main relay (IGP).
    2. NO  - Repair open in the wire between the PGM-FI main relay (IGP) and the ECM (A8).
  41. Turn the ignition switch ON (II).
  42. Measure voltage between body ground and ECM connector terminals B1 and B9 individually.
    Fig 14: Measuring Voltage Between Body Ground And ECM Connector Terminals B1 And B9
    G03680930Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    1. YES  - Go to step  49.
    2. NO  - Go to step 43.
  43. Turn the ignition switch OFF.
  44. Remove the PGM-FI main relay (IGP).
  45. Turn the ignition switch ON (II).
  46. Measure voltage between PGM-FI main relay (IGP) 4P connector terminal No. 2 and body ground.
    Fig 15: Measuring Voltage Between PGM-FI Main Relay (IGP) 4P Connector Terminal No. 2 And Body Ground
    G03680931Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    1. YES  - Go to step 47.
    2. NO  - Repair open in the wire between the No. 7 (15 A) fuse and the PGM-FI main relay (IGP).
  47. Turn the ignition switch OFF.
  48. Check for continuity between PGM-FI main relay (IGP) 4P connector terminal No. 1 and ECM connector terminals B1 and B9 individually.
    Fig 16: Checking Continuity Between PGM-FI Main Relay (IGP) 4P Connector Terminal No. 1 And ECM Connector Terminals B1 And B9
    G03680932Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    1. YES  - Replace the PGM-FI main relay (IGP).
    2. NO  - Repair open in the wire between the PGM-FI main relay (IGP) and the ECM (B1, B9).
  49. Measure voltage between body ground and ECM connector terminals B2, B10, B20, and B22 individually.
    Fig 17: Measuring Voltage Between Body Ground And ECM Connector Terminals
    G03680933Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there more than 1.0 V? 

    1. YES  - Repair open in the wire(s) that had more than 1.0 V between G101 and the ECM (B2, B10, B20, B22).
    2. NO  - Go to step 50.
  50. Measure voltage between body ground and ECM connector terminal C19.
    Fig 18: Measuring Voltage Between Body Ground And ECM Connector Terminal C19
    G03680934Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there about 5 V? 

    1. YES  - Go to step  58.
    2. NO  - Go to step 51.
  51. Turn the ignition switch OFF.
  52. Disconnect the manifold absolute pressure (MAP) sensor 3P connector.
  53. Turn the ignition switch ON (II).
  54. Measure voltage between body ground and ECM connector terminal C19.
    Fig 19: Measuring Voltage Between Body Ground And ECM Connector Terminal C19
    G03680935Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there about 5 V? 

    1. YES  - Replace the MAP sensor.
    2. NO  - Go to step 55.
  55. Turn the ignition switch OFF, and wait for 10 seconds.
  56. Disconnect ECM connector C (31P).
  57. Check for continuity between ECM connector terminal C19 and body ground.
    Fig 20: Checking Continuity Between ECM Connector Terminal C19 And Body Ground
    G03680936Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    1. YES  - Repair short in the wire between the ECM (C19) and the MAP sensor.
    2. NO  - Update the ECM if it does not have the latest software, or substitute a known-good ECM (see ECM UPDATING AND SUBSTITUTION FOR TESTING-2002-2006 M/T MODELS AND CVT MODEL ), then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM (see ECM REPLACEMENT ).
  58. Measure voltage between body ground and ECM connector terminal C28.
    Fig 21: Measuring Voltage Between Body Ground And ECM Connector Terminal C28
    G03680937Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there about 5 V? 

    1. YES  -
      • M/T model: Go to step  65.
      • CVT model: Go to step  73.
    2. NO  - Go to step 59.
  59. Turn the ignition switch OFF.
  60. Disconnect the 3P connector from each of these sensors, one at a time, and measure voltage between body ground and ECM connector terminal C28 with the ignition switch ON (II).
    • Exhaust gas recirculation (EGR) valve position sensor
    • Brake booster pressure sensor
    • Fuel tank pressure (FTP) sensor
    • Throttle position (TP) sensor
    • Brake fluid pressure sensor A (M/T model)
    Fig 22: Measuring Voltage Between Body Ground And ECM Connector Terminal C28 With Ignition Switch ON (II)
    G03680938Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there about 5 V? 

    1. YES  - Replace the sensor that restored about 5 V when disconnected.
    2. NO  - Go to step 61.
  61. Turn the ignition switch OFF.
  62. Disconnect the connector from these sensors:
    • Exhaust gas recirculation (EGR) valve position sensor
    • Brake booster pressure sensor
    • Fuel tank pressure (FTP) sensor
    • Throttle position (TP) sensor
    • Brake fluid pressure sensor A (M/T model)
  63. Disconnect ECM connector C (31P).
  64. Check for continuity between ECM connector terminal C28 and body ground.
    Fig 23: Checking Continuity Between ECM Connector Terminal C28 And Body Ground
    G03680939Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    1. YES  - Repair short in the wire between the ECM (C28) and the EGR valve position sensor, the brake booster pressure sensor, the FTP sensor, the TP sensor, or brake fluid pressure sensor A (M/T model).
    2. NO  - Update the ECM if it does not have the latest software, or substitute a known-good ECM (see ECM UPDATING AND SUBSTITUTION FOR TESTING-2002-2006 M/T MODELS AND CVT MODEL ), then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM (see ECM REPLACEMENT ).
  65. Measure voltage between body ground and ECM connector terminal C23.
    Fig 24: Measuring Voltage Between Body Ground And ECM Connector Terminal C23
    G03680940Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there about 5 V? 

    1. YES  - Update the ECM if it does not have the latest software, or substitute a known-good ECM (see ECM UPDATING AND SUBSTITUTION FOR TESTING-2002-2006 M/T MODELS AND CVT MODEL ), then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM (see ECM REPLACEMENT ).
    2. NO  - Go to step 66.
  66. Turn the ignition switch OFF.
  67. Disconnect the brake fluid pressure sensor B 3P connector.
  68. Turn the ignition switch ON (II).
  69. Measure voltage between body ground and ECM connector terminal C23.
    Fig 25: Measuring Voltage Between Body Ground And ECM Connector Terminal C23
    G03680941Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there about 5 V? 

    1. YES  - Replace brake fluid pressure sensor B.
    2. NO  - Go to step 70.
  70. Turn the ignition switch OFF, and wait for 10 seconds.
  71. Disconnect ECM connector C (31P).
  72. Check for continuity between ECM connector terminal C23 and body ground.
    Fig 26: Checking Continuity Between ECM Connector Terminal C23 And Body Ground
    G03680942Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    1. YES  - Repair short in the wire between the ECM (C23) and brake fluid pressure sensor B.
    2. NO  - Update the ECM if it does not have the latest software, or substitute a known-good ECM (see ECM UPDATING AND SUBSTITUTION FOR TESTING-2002-2006 M/T MODELS AND CVT MODEL ), then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM (see ECM REPLACEMENT ).
  73. Measure voltage between body ground and ECM connector terminal B6.
    Fig 27: Measuring Voltage Between Body Ground And ECM Connector Terminal B6
    G03680943Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there about 5 V? 

    1. YES  - Update the ECM if it does not have the latest software, or substitute a known-good ECM (see ECM UPDATING AND SUBSTITUTION FOR TESTING-2002-2006 M/T MODELS AND CVT MODEL ), then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM (see ECM REPLACEMENT ).
    2. NO  - Go to step 74.
  74. Turn the ignition switch OFF.
  75. Disconnect TCM connector B (22P).
  76. Turn the ignition switch ON (II).
  77. Measure voltage between body ground and ECM connector terminal B6.
    Fig 28: Measuring Voltage Between Body Ground And ECM Connector Terminal B6
    G03680944Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there about 5 V? 

    1. YES  - Substitute a known-good TCM, and recheck (see HOW TO TROUBLESHOOT CIRCUIT AT THE TCM ). If the symptom/indication goes away, replace the original TCM.
    2. NO  - Go to step 78.
  78. Turn the ignition switch OFF, and wait for 10 seconds.
  79. Disconnect ECM connector B (25P).
  80. Check for continuity between ECM connector terminal B6 and body ground.
    Fig 29: Checking Continuity Between ECM Connector Terminal B6 And Body Ground
    G03680945Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    1. YES  - Repair short in the wire between the ECM (B6) and the TCM (B20).
    2. NO  - Update the ECM if it does not have the latest software, or substitute a known-good ECM (see ECM UPDATING AND SUBSTITUTION FOR TESTING-2002-2006 M/T MODELS AND CVT MODEL ), then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM (see ECM REPLACEMENT ).
  81. Measure voltage between ECM connector terminal B17 and body ground.
    Fig 30: Measuring Voltage Between ECM Connector Terminal B17 And Body Ground
    G03680946Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there about 5 V (or battery voltage)? 

    1. YES  - Go to step  85.
    2. NO  - Go to step 82.
  82. Turn the ignition switch OFF, and wait for 10 seconds.
  83. Disconnect ECM connector B (25P).
  84. Check for continuity between ECM connector terminal B17 and body ground.
    Fig 31: Checking Continuity Between ECM Connector Terminal B17 And Body Ground
    G03680947Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    1. YES  - Repair short in the wire between the DLC and the ECM (B17).
    2. NO  - Update the ECM if it does not have the latest software, or substitute a known-good ECM (see ECM UPDATING AND SUBSTITUTION FOR TESTING-2002-2006 M/T MODELS AND CVT MODEL ), then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM (see ECM REPLACEMENT ).
  85. Turn the ignition switch OFF, and wait for 10 seconds.
  86. Disconnect ECM connector B (25P).
  87. Turn the ignition switch ON (II).

    Is the MIL on? 

    1. YES  - Repair short in the wire between the gauge assembly and the ECM (B17). If the wire is OK, replace the gauge assembly.
    2. NO  - Update the ECM if it does not have the latest software, or substitute a known-good ECM (see ECM UPDATING AND SUBSTITUTION FOR TESTING-2002-2006 M/T MODELS AND CVT MODEL ), then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM (see ECM REPLACEMENT ).
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