LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Acura >> 2009 >> RDX >> Repair and Diagnosis >> Engine Performance >> System >> Fuel Supply System >> DTC Troubleshooting >> DTC P0627: Fuel Pump Control Module System Malfunction
April 5, 2026: LEMON Manuals is launched! Read the announcement.

DTC P0627: Fuel Pump Control Module System Malfunction

NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION ).
  1. Turn the ignition switch ON (II).
  2. Clear the DTC with the HDS.
  3. Turn the ignition switch to the start (III) position.
    NOTE:
    • If the engine starts, release the ignition switch.
    • If the engine does not start, do not keep cranking for more than 10 seconds.
  4. Check for Temporary DTCs or DTCs with the HDS.

    Is DTC P0627 indicated? 

    YES  - Go to step  5.

    NO  - Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the fuel pump control module, PGM-FI main relay 2 (FUEL PUMP), the fuel pump, and the PCM.

  5. Turn the ignition switch OFF.
  6. Check the No. 2 FUEL PUMP (20 A) fuse in under-dash fuse/relay box.

    Is the fuse blown? 

    YES  - Repair short in the wire between PGM-FI main relay 2 (FUEL PUMP) and the No. 2 FUEL PUMP (20 A) fuse. Also replace the No. 2 FUEL PUMP (20 A) fuse, then go to step  79.

    NO  - Go to step  7.

  7. Disconnect the fuel pump control module 10P connector (see FUEL PUMP CONTROL MODULE REPLACEMENT ).
  8. Turn the ignition switch ON (II), and measure voltage between fuel pump control module 10P connector terminals No. 3 and No. 8 within 2 seconds.
    Fig 1: Measuring Voltage Between Fuel Pump Control Module 10P Connector Terminals No. 3 And No. 8
    G05444694Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  - Go to step  35.

    NO  - Go to step  9.

  9. Turn the ignition switch OFF.
  10. Remove the driver's dashboard under cover (see DRIVER'S DASHBOARD UNDERCOVER REMOVAL/INSTALLATION ), then remove PGM-FI main relay 2 (FUEL PUMP) (A) from the under-dash fuse/relay box.
    Fig 2: Identifying PGM-FI Main Relay 2 (Fuel Pump)
    G05444695Courtesy of AMERICAN HONDA MOTOR CO., INC.
  11. Test PGM-FI main relay 2 (FUEL PUMP) (see POWER RELAY TEST ).

    Is PGM-FI main relay 2 (FUEL PUMP) OK? 

    YES  - Go to step  12.

    NO  - Replace PGM-FI main relay 2 (FUEL PUMP), then go to step  79.

  12. Turn the ignition switch ON (II).
  13. Measure voltage between PGM-FI main relay 2 (FUEL PUMP) 4P connector terminal No. 4 and body ground.
    Fig 3: Measuring Voltage Between PGM-FI Main Relay 2 (Fuel Pump) 4P Connector Terminal No. 4 And Body Ground
    G05444696Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  - Go to step  20.

    NO  - Go to step  14.

  14. Turn the ignition switch OFF.
  15. Disconnect the under-hood fuse/relay box 10P connector.
  16. Disconnect the engine wire harness 23P connector.
  17. Disconnect the under-dash fuse/relay box 21P connector.
  18. Connect under-dash fuse/relay box 21P connector terminal No. 4 to body ground with a jumper wire.
    Fig 4: Connecting Under-Dash Fuse/Relay Box 21P Connector Terminal No. 4 To Body Ground With Jumper Wire
    G05444697Courtesy of AMERICAN HONDA MOTOR CO., INC.
  19. Check for continuity between under-hood fuse/relay box 10P connector terminal No. 5 and body ground.
    Fig 5: Checking Continuity Between Under-Hood Fuse/Relay Box 10P Connector Terminal No. 5 And Body Ground
    G05444698Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -

    NO  - Repair open in the wire between the under-hood fuse/relay box and the under-dash fuse/relay box.

  20. Measure voltage between PGM-FI main relay 2 (FUEL PUMP) 4P connector terminal No. 1 and body ground.
    Fig 6: Measuring Voltage Between PGM-FI Main Relay 2 (Fuel Pump) 4P Connector Terminal No. 1 And Body Ground
    G05444699Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  - Go to step  21.

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

  21. Turn the ignition switch OFF.
  22. Connect PGM-FI main relay 2 (FUEL PUMP) 4P connector terminals No. 1 and No. 2 with a jumper wire.
    Fig 7: Connecting PGM-FI Main Relay 2 (Fuel Pump) 4P Connector Terminals No. 1 And No. 2 With Jumper Wire
    G05444700Courtesy of AMERICAN HONDA MOTOR CO., INC.
  23. Turn the ignition switch ON (II), and measure voltage between fuel pump control module 10P connector terminal No. 3 and body ground.
    Fig 8: Measuring Voltage Between Fuel Pump Control Module 10P Connector Terminal No. 3 And Body Ground
    G05444701Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  - Go to step  24.

    NO  -

    • Repair open in the wire between the under-dash fuse/relay box and the fuel pump control module, then go to step  79.
    • If needed, replace the under-dash fuse/relay box (see REMOVAL AND INSTALLATION ), then go to step  79.
  24. Turn the ignition switch OFF.
  25. Jump the SCS line with the HDS.
  26. Disconnect PCM connector A (44P).
  27. Connect PGM-FI main relay 2 (FUEL PUMP) 4P connector terminal No. 3 to body ground with a jumper wire.
    Fig 9: Connecting PGM-FI Main Relay 2 (Fuel Pump) 4P Connector Terminal No. 3 To Body Ground With Jumper Wire
    G05444702Courtesy of AMERICAN HONDA MOTOR CO., INC.
  28. Check for continuity between PCM connector terminal A15 and body ground.
    Fig 10: Checking Continuity Between PCM Connector Terminal A15 And Body Ground
    G05444703Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Go to step  29.

    NO  - Repair open in the wire between the PCM (A15) and PGM-FI main relay 2 (FUEL PUMP), then go to step  79.

  29. Remove the jumper wire.
  30. Reinstall PGM-FI main relay 2 (FUEL PUMP).
  31. Reconnect PCM connector A (44P).
  32. Open SCS line with the HDS.
  33. Turn the ignition switch ON (II), and measure voltage between under-dash fuse/relay box 34P connector terminal No. 10 and body ground within 2 seconds.
    Fig 11: Measuring Voltage Between Under-Dash Fuse/Relay Box 34P Connector Terminal No. 10 And Body Ground
    G05444704Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    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  - Go to step  34.

  34. Turn the ignition switch ON (II), and measure voltage between under-dash fuse/relay box 34P connector terminal No. 10 and body ground after 2 seconds.
    Fig 12: Measuring Voltage Between Under-Dash Fuse/Relay Box 34P Connector Terminal No. 10 And Body Ground
    G05444705Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  - Go to step  85.

    NO  - If needed, replace the under-dash fuse/relay box (see REMOVAL AND INSTALLATION ), then go to step  79.

  35. Turn the ignition switch OFF.
  36. Reconnect the fuel pump control module 10P connector (see FUEL PUMP CONTROL MODULE REPLACEMENT ).
  37. Turn the ignition switch ON (II).
  38. Clear the DTC with the HDS.
  39. Turn the ignition switch OFF.
  40. Turn the ignition switch ON (II), and check for sound from the fuel pump within 2 seconds.

    Does the fuel pump operate? 

    YES  - Go to step  41.

    NO  - Go to step  60.

  41. Turn the ignition switch OFF.
  42. Disconnect the fuel pump control module 10P connector.
  43. Check for continuity between fuel pump control module 10P connector terminal No. 4 and body ground.
    Fig 13: Checking Continuity Between Fuel Pump Control Module 10P Connector Terminal No. 4 And Body Ground
    G05444706Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Go to step  44.

    NO  - Go to step  47.

  44. Jump the SCS line with the HDS.
  45. Disconnect PCM connector A (44P).
  46. Check for continuity between PCM connector terminal A38 and body ground.
    Fig 14: Checking Continuity Between PCM Connector Terminal A38 And Body Ground
    G05444707Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Repair short in the wire between the PCM (A38) and the fuel pump control module, then go to step  79.

    NO  - Go to step  86.

  47. Jump the SCS line with the HDS.
  48. Disconnect PCM connector A (44P).
  49. Connect fuel pump control module 10P connector terminal No. 4 to body ground with a jumper wire.
    Fig 15: Connecting Fuel Pump Control Module 10P Connector Terminal No. 4 To Body Ground With Jumper Wire
    G05444708Courtesy of AMERICAN HONDA MOTOR CO., INC.
  50. Check for continuity between PCM connector terminal A38 and body ground.
    Fig 16: Checking Continuity Between PCM Connector Terminal A38 And Body Ground
    G05444709Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Go to step  51.

    NO  - Repair open in the wire between the PCM (A38) and the fuel pump control module, then go to step  79.

  51. Remove the jumper wire from the fuel pump control module 10P connector.
  52. Reconnect the fuel pump control module 10P connector and PCM connector A (44P).
  53. Turn the ignition switch ON (II).
  54. Measure voltage between fuel pump control module 10P connector terminal No. 4 and body ground.
    Fig 17: Measuring Voltage Between Fuel Pump Control Module 10P Connector Terminal No. 4 And Body Ground
    G05444710Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there about 8 V or more? 

    YES  - Go to step  55.

    NO  - Replace the fuel pump control module (see FUEL PUMP CONTROL MODULE REPLACEMENT ), then go to step  79.

  55. Turn the ignition switch OFF.
  56. Fold the rear seat down, then remove the left rear door sill trim (see REAR DOOR SILL AREA ).
  57. Pull back the carpet to expose the access panel (see step 9 under CARPET REPLACEMENT ), then remove the access panel from the left side of the floor (see FUEL TANK UNIT REMOVAL AND INSTALLATION ).
  58. Disconnect the fuel pump 4P connector.
  59. Check for continuity between fuel pump control module 10P connector terminal No. 7 and body ground.
    Fig 18: Checking Continuity Between Fuel Pump Control Module 10P Connector Terminal No. 7 And Body Ground
    G05444711Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Repair short in the wire between the fuel pump control module (FP- line) and the fuel pump, then go to step  79.

    NO  - Substitute a known-good fuel pump control module (see FUEL PUMP CONTROL MODULE REPLACEMENT ), then go to step  79 and recheck. If DTC P0627 is not indicated, replace the original fuel pump control module (see FUEL PUMP CONTROL MODULE REPLACEMENT ), then go to step  79. If DTC P0627 is indicated, go to step  85.

  60. Turn the ignition switch OFF.
  61. Disconnect the fuel pump control module 10P connector (see FUEL PUMP CONTROL MODULE REPLACEMENT ).
  62. Check for continuity between fuel pump control module 10P connector terminal No. 5 and body ground.
    Fig 19: Checking Continuity Between Fuel Pump Control Module 10P Connector Terminal No. 5 And Body Ground
    G05444712Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Go to step  63.

    NO  - Go to step  66.

  63. Jump the SCS line with the HDS.
  64. Disconnect PCM connector A (44P).
  65. Check for continuity between PCM connector terminal A43 and body ground.
    Fig 20: Checking Continuity Between PCM Connector Terminal A43 And Body Ground
    G05444713Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Repair short in the wire between the PCM (A43) and the fuel pump control module, then go to step  79.

    NO  - Go to step  86.

  66. Reconnect the fuel pump control module 10P connector.
  67. Turn the ignition switch ON (II), and measure voltage between fuel pump control module 10P connector terminal No. 5 and body ground within 2 seconds.
    Fig 21: Measuring Voltage Between Fuel Pump Control Module 10P Connector Terminal No. 5 And Body Ground
    G05444714Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  - Go to step  68.

    NO  - Replace the fuel pump control module (see FUEL PUMP CONTROL MODULE REPLACEMENT ), then go to step  79.

  68. Turn the ignition switch OFF.
  69. Fold the rear seat down, then remove the left rear door sill trim (see REAR DOOR SILL AREA ).
  70. Pull back the carpet to expose the access panel (see step 9 under CARPET REPLACEMENT ), then remove the access panel from the left side of the floor (see FUEL TANK UNIT REMOVAL AND INSTALLATION ).
  71. Disconnect the fuel tank unit 4P connector.
  72. Disconnect the fuel pump control module 10P connector (see FUEL PUMP CONTROL MODULE REPLACEMENT ).
  73. Connect fuel tank unit 4P connector terminal No. 2 to body ground with a jumper wire.
    Fig 22: Connecting Fuel Tank Unit 4P Connector Terminal No. 2 To Body Ground With Jumper Wire
    G05444715Courtesy of AMERICAN HONDA MOTOR CO., INC.
  74. Check for continuity between fuel pump control module 10P connector terminal No. 6 and body ground.
    Fig 23: Checking Continuity Between Fuel Pump Control Module 10P Connector Terminal No. 6 And Body Ground
    G05444716Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Go to step  75.

    NO  - Repair open in the wire between the fuel pump control module (FP+ line) and the fuel pump, then go to step  79.

  75. Remove the jumper wire from the fuel tank unit 4P connector terminal No. 2, then connect between fuel tank unit 4P connector terminal No. 4 to body ground with a jumper wire.
    Fig 24: Connecting Between Fuel Tank Unit 4P Connector Terminal No. 4 To Body Ground With Jumper Wire
    G05444717Courtesy of AMERICAN HONDA MOTOR CO., INC.
  76. Check for continuity between fuel pump control module 10P connector terminal No. 7 and body ground.
    Fig 25: Checking Continuity Between Fuel Pump Control Module 10P Connector Terminal No. 7 And Body Ground
    G05444718Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Go to step  77.

    NO  - Repair open in the wire between the fuel pump control module (FP- line) and the fuel pump, then go to step  79.

  77. Remove the jumper wire from the fuel tank unit 4P connector terminal No. 4, and reconnect the fuel pump control module 10P connector.
  78. Turn the ignition switch ON (II), and measure voltage between fuel tank unit 4P connector terminal No. 2 and body ground within 2 seconds.
    Fig 26: Measuring Voltage Between Fuel Tank Unit 4P Connector Terminal No. 2 And Body Ground
    G05444719Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  - Replace the fuel pump (see FUEL PUMP/FUEL GAUGE SENDING UNIT REPLACEMENT ), then go to step  79.

    NO  - Substitute a known-good fuel pump control module (see FUEL PUMP CONTROL MODULE REPLACEMENT ), then go to step  79 and recheck. If DTC P0627 is not indicated, replace the original fuel pump control module (see FUEL PUMP CONTROL MODULE REPLACEMENT ), then go to step  79. If DTC P0627 is indicated, go to step  85.

  79. Turn the ignition switch OFF.
  80. Reconnect all connectors.
  81. Turn the ignition switch ON (II).
  82. Reset the PCM with the HDS.
  83. Do the PCM idle learn procedure (see PCM IDLE LEARN PROCEDURE ).
  84. Check for Temporary DTCs or DTCs with the HDS.

    Is DTC P0627 indicated? 

    YES  - Check for poor connections or loose terminals at the fuel pump control module, PGM-FI main relay 2 (FUEL PUMP), the fuel pump, and the PCM, then go to step  1.

    NO  - Troubleshooting is complete. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTCs troubleshooting.

  85. Turn the ignition switch OFF.
  86. Reconnect all connectors.
  87. Update the PCM if it does not have the latest software (see PCM UPDATE ), or substitute a known-good PCM (see SUBSTITUTING THE PCM ).
  88. Check for Temporary DTCs or DTCs with the HDS.

    Is DTC P0627 indicated? 

    YES  - Check for poor connections or loose terminals at the fuel pump control module, PGM-FI main relay 2 (FUEL PUMP), the fuel pump, and the PCM. If the PCM was updated, substitute a known-good PCM (see SUBSTITUTING THE PCM ), then recheck. If the PCM was substituted, go to step  1.

    NO  - If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the original PCM (see PCM REPLACEMENT ). If any other Temporary DTCs or DTCs are indicated, go to the indicated DTCs troubleshooting.

scientia non olet · About LEMON Manuals