Fuel Supply System Acura RDX I

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DTC P0461: Fuel Level Sensor (Fuel Gauge Sending Unit) Circuit Range/Performance Problem

Note. Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION ). Because it requires 162 miles (260 km) of driving without refueling to complete this diagnosis, DTC P0461 cannot be duplicated during this troubleshooting.

1. Test the fuel gauge sending unit (see «FUEL GAUGE SENDING UNIT TEST»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system__fuel-gauge-sending-unit-test) ). Is the fuel gauge sending unit OK? YES - Check for poor connections or loose terminals at the fuel gauge sending unit and the gauge control module. NO - Replace the fuel gauge sending unit (see «FUEL PUMP/FUEL GAUGE SENDING UNIT REPLACEMENT»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system) ), then go to step 2 .
2. Turn the ignition switch ON (II).
3. Reset the PCM with the HDS.
4. Do the PCM idle learn procedure (see «PCM IDLE LEARN PROCEDURE»(/acura/rdx/i-2006-2009/remont/engine-control-systems/#idle-control-system__pcm-idle-learn-procedure) ).
5. Check for Temporary DTCs or DTCs with the HDS. Is DTC P0461 indicated? YES - Check for poor connections or loose terminals at the fuel gauge sending unit and the gauge control module, then go to step 1 . NO - Troubleshooting is complete. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTCs troubleshooting.

DTC P0462: Fuel Level Sensor (Fuel Gauge Sending Unit) Circuit Low Voltage

Note. Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION ).

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1. Turn the ignition switch ON (II).
2. Clear the DTC with the HDS, and wait 5 seconds.
3. Check for Temporary DTCs or DTCs with the HDS. Is DTC P0462 indicated? YES - Go to step 4 . NO - Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the gauge control module, the fuel gauge sending unit, and the secondary fuel gauge sending unit.
4. Turn the ignition switch OFF.
5. Fold the rear seat down, then remove the right rear side garnish (see «TRIM REMOVAL/INSTALLATION - REAR SIDE AREA»(/acura/rdx/i-2006-2009/remont/exteriorinterior-trim/#interior-trim__trim-removalinstallation-rear-side-area) ).
6. Pull back the carpet to expose the access panel (see step 9 under «CARPET REPLACEMENT»(/acura/rdx/i-2006-2009/remont/exteriorinterior-trim/#interior-trim__carpet-replacement) ), then remove the access panel from the right side of the floor (see «SECONDARY FUEL GAUGE SENDING UNIT REMOVAL/INSTALLATION»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system__secondary-fuel-gauge-sending-unit-removalinstallation) ).
7. Disconnect the secondary fuel gauge sending unit 4P connector.
8. Turn the ignition switch ON (II).
9. Clear the DTC with the HDS, and wait 5 seconds.
10. Check for Temporary DTCs or DTCs with the HDS. Is DTC P0463 indicated? YES - Check the secondary fuel gauge sending unit (see «SECONDARY FUEL GAUGE SENDING UNIT TEST»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system) ), then go to step 30 . NO - Go to step 11 .
11. Turn the ignition switch OFF.
12. Remove the left rear door sill trim (see «REAR DOOR SILL AREA»(/acura/rdx/i-2006-2009/remont/exteriorinterior-trim/#interior-trim__rear-door-sill-area) ), then remove the access panel from the left side of the floor (see «FUEL TANK UNIT REMOVAL AND INSTALLATION»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system__fuel-tank-unit-removal-and-installation) ).
13. Disconnect the fuel tank unit 4P connector.
14. Turn the ignition switch ON (II).
15. Clear the DTC with the HDS, and wait 5 seconds.
16. Check for Temporary DTCs or DTCs with the HDS. Is DTC P0463 indicated? YES - Go to step 20. NO - Go to step 17.
17. Turn the ignition switch lock (0).
18. Remove the gauge control module (see «GAUGE CONTROL MODULE REPLACEMENT»(/acura/rdx/i-2006-2009/remont/gauges-instrument-panels/#gauges__gauge-control-module-replacement) ).
19. Check for continuity between fuel tank unit 4P connector terminal No. 1 and body ground. Is there continuity? YES - Repair short in the wire between the gauge control module (signal line) and the fuel gauge sending unit, then go to step 30 . NO - Go to step 22 .
20. Turn the ignition switch TO LOCK (0).
21. Check for continuity between fuel tank unit 4P connector terminal No. 3 and body ground. Is there continuity? YES - Repair short in the wire between the fuel gauge sending unit and secondary fuel gauge sending unit, then go to step 30 . NO - Check the fuel gauge sending unit (see «FUEL GAUGE SENDING UNIT TEST»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system__fuel-gauge-sending-unit-test) ).
22. Reconnect the gauge control module 36P connector.
23. Remove the fuel tank unit (see «FUEL TANK UNIT REMOVAL AND INSTALLATION»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system__fuel-tank-unit-removal-and-installation) ) and the secondary fuel gauge sending unit (see «SECONDARY FUEL GAUGE SENDING UNIT REMOVAL/INSTALLATION»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system__secondary-fuel-gauge-sending-unit-removalinstallation) )
24. Connect the fuel tank unit and secondary fuel gauge sending unit 4P connectors.
25. Turn the ignition switch ON (II).
26. Clear the DTC with the HDS.
27. Set the floats (A) to the E position.
28. Check the fuel gauge. Does the gauge move to the empty position? YES - Go to step 36 . NO - Replace the gauge control module (see «GAUGE CONTROL MODULE REPLACEMENT»(/acura/rdx/i-2006-2009/remont/gauges-instrument-panels/#gauges__gauge-control-module-replacement) ), then go to step 29 .
29. Turn the ignition switch OFF.
30. Install the parts in the reverse order of removal.
31. Reconnect all connectors.
32. Turn the ignition switch ON (II).
33. Reset the PCM with the HDS.
34. Do the PCM idle learn procedure (see «PCM IDLE LEARN PROCEDURE»(/acura/rdx/i-2006-2009/remont/engine-control-systems/#idle-control-system__pcm-idle-learn-procedure) ).
35. Check for Temporary DTCs or DTCs with the HDS. Is DTC P0462 indicated? YES - Check for poor connections or loose terminals at the gauge control module, the fuel gauge sending unit, and the secondary fuel gauge sending unit, then go to step 1 . NO - Troubleshooting is complete. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTCs troubleshooting.
36. Reconnect all connectors.
37. Update the PCM if it does not have the latest software (see «PCM UPDATE»(/acura/rdx/i-2006-2009/remont/testing-diagnostics/#pgm-fi-system__pcm-update) ), or substitute a known-good PCM (see «SUBSTITUTING THE PCM»(/acura/rdx/i-2006-2009/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__substituting-the-pcm) ).
38. Check for Temporary DTCs or DTCs with the HDS. Is DTC P0462 indicated? YES - Check for poor connections or loose terminals at the gauge control module, the fuel gauge sending unit, and the secondary fuel gauge sending unit. If the PCM was updated, substitute a known-good PCM (see «SUBSTITUTING THE PCM»(/acura/rdx/i-2006-2009/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__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»(/acura/rdx/i-2006-2009/remont/testing-diagnostics/#pgm-fi-system__pcm-replacement) ). If any other Temporary DTCs or DTCs are indicated, go to the indicated DTCs troubleshooting.

DTC P0463: Fuel Level Sensor (Fuel Gauge Sending Unit) Circuit High Voltage

Note. Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION ).

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1. Turn the ignition switch ON (II).
2. Clear the DTC with the HDS, and wait 5 seconds.
3. Check for Temporary DTCs or DTCs with the HDS. Is DTC P0463 indicated? YES - Go to step 4 . NO - Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the gauge control module, the fuel gauge sending unit, and the secondary fuel gauge sending unit.
4. Turn the ignition switch OFF.
5. Fold the rear seat down, then remove the rear door sill trim (see «REAR DOOR SILL AREA»(/acura/rdx/i-2006-2009/remont/exteriorinterior-trim/#interior-trim__rear-door-sill-area) ).
6. Pull back the carpet to expose the access panel (see step 9 under «CARPET REPLACEMENT»(/acura/rdx/i-2006-2009/remont/exteriorinterior-trim/#interior-trim__carpet-replacement) ), then remove the access panel from the left side of the floor (see «FUEL TANK UNIT REMOVAL AND INSTALLATION»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system__fuel-tank-unit-removal-and-installation) ).
7. Disconnect the fuel tank unit 4P connector.
8. Remove the access panel from the right side of the floor (see «SECONDARY FUEL GAUGE SENDING UNIT REMOVAL/INSTALLATION»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system__secondary-fuel-gauge-sending-unit-removalinstallation) ).
9. Disconnect the secondary fuel gauge sending unit 4P connector.
10. Check for continuity between fuel tank unit 4P connector terminal No. 3 and the secondary fuel gauge sending unit 4P connector terminal No. 1. Is there continuity? YES - Go to step 11 . NO - Repair open in the wire between the fuel gauge sending unit and the secondary fuel gauge sending unit, then go to step 26 .
11. Remove the gauge control module (see «GAUGE CONTROL MODULE REPLACEMENT»(/acura/rdx/i-2006-2009/remont/gauges-instrument-panels/#gauges__gauge-control-module-replacement) ).
12. Connect secondary fuel gauge sending unit 4P connector terminal No. 3 to body ground with a jumper wire.
13. Check for continuity between gauge control module 36P connector terminal No. 20 and body ground. Is there continuity? YES - Go to step 14 . NO - Repair open in the wire between the gauge control module and the secondary fuel gauge sending unit, then go to step 26 .
14. Connect fuel tank unit 4P connector terminal No. 1 to body ground with a jumper wire.
15. Check for continuity between gauge control module 36P connector terminal No. 27 and body ground. Is there continuity? YES - Go to step 16 . NO - Repair open in the wire between the gauge control module and the fuel gauge sending unit, then go to step 26 .
16. Disconnect the jumper wire from the fuel gauge sending unit 4P connector.
17. Remove the fuel tank unit (see «FUEL TANK UNIT REMOVAL AND INSTALLATION»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system__fuel-tank-unit-removal-and-installation) ).
18. Test the fuel gauge sending unit (see «FUEL GAUGE SENDING UNIT TEST»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system__fuel-gauge-sending-unit-test) ). Is the fuel gauge sending unit OK? YES - Go to step 19 . NO - Replace the fuel gauge sending unit (see «FUEL PUMP/FUEL GAUGE SENDING UNIT REPLACEMENT»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system) ), then go to step 26 .
19. Remove the secondary fuel gauge sending unit (see «SECONDARY FUEL GAUGE SENDING UNIT REMOVAL/INSTALLATION»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system__secondary-fuel-gauge-sending-unit-removalinstallation) ).
20. Test the secondary fuel gauge sending unit (see «SECONDARY FUEL GAUGE SENDING UNIT TEST»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system) ). Is the secondary fuel gauge sending unit OK? YES - Go to step 21 . NO - Replace the secondary fuel gauge sending unit (see «SECONDARY FUEL GAUGE SENDING UNIT REMOVAL/INSTALLATION»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system__secondary-fuel-gauge-sending-unit-removalinstallation) ), then go to step 26 .
21. Reconnect the fuel tank unit 4P connector, the secondary fuel gauge sending unit 4P connector, and the gauge control module 36P connector.
22. Turn the ignition switch ON (II).
23. Set the floats (A) to the F position.
24. Check the fuel gauge. Does the gauge move to the full position? YES - Go to step 32 . NO - Replace the gauge control module (see «GAUGE CONTROL MODULE REPLACEMENT»(/acura/rdx/i-2006-2009/remont/gauges-instrument-panels/#gauges__gauge-control-module-replacement) ), then go to step 25 .
25. Turn the ignition switch OFF.
26. Install the parts in the reverse order of removal.
27. Reconnect all connectors.
28. Turn the ignition switch ON (II).
29. Reset the PCM with the HDS.
30. Do the PCM idle learn procedure (see «PCM IDLE LEARN PROCEDURE»(/acura/rdx/i-2006-2009/remont/engine-control-systems/#idle-control-system__pcm-idle-learn-procedure) ).
31. Check for Temporary DTCs or DTCs with the HDS. Is DTC P0463 indicated? YES - Check for poor connections or loose terminals at the gauge control module, the fuel gauge sending unit, and the secondary fuel gauge sending unit, then go to step 1 . NO - Troubleshooting is complete. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTCs troubleshooting.
32. Reconnect all connectors.
33. Update the PCM if it does not have the latest software (see «PCM UPDATE»(/acura/rdx/i-2006-2009/remont/testing-diagnostics/#pgm-fi-system__pcm-update) ), or substitute a known-good PCM (see «SUBSTITUTING THE PCM»(/acura/rdx/i-2006-2009/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__substituting-the-pcm) ).
34. Check for Temporary DTCs or DTCs with the HDS. Is DTC P0463 indicated? YES - Check for poor connections or loose terminals at the gauge control module, the fuel gauge sending unit, and the secondary fuel gauge sending unit. If the PCM was updated, substitute a known-good PCM (see «SUBSTITUTING THE PCM»(/acura/rdx/i-2006-2009/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__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»(/acura/rdx/i-2006-2009/remont/testing-diagnostics/#pgm-fi-system__pcm-replacement) ). If any other Temporary DTCs or DTCs are indicated, go to the indicated DTCs troubleshooting.

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 ).

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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»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system) ).
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. 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»(/acura/rdx/i-2006-2009/remont/gauges-instrument-panels/#dashboard-instrument-panel__drivers-dashboard-undercover-removalinstallation) ), then remove PGM-FI main relay 2 (FUEL PUMP) (A) from the under-dash fuse/relay box.
11. Test PGM-FI main relay 2 (FUEL PUMP) (see «POWER RELAY TEST»(/acura/rdx/i-2006-2009/remont/body-electrical/#relays__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. 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.
19. Check for continuity between under-hood fuse/relay box 10P connector terminal No. 5 and body ground. Is there continuity? YES - Replace PGM-FI main relay 1. If needed, replace the under-hood fuse/relay box (see «REMOVAL AND INSTALLATION»(/acura/rdx/i-2006-2009/remont/body-electrical/#under-hood-fuserelay-box) ). 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. Is there battery voltage? YES - Go to step 21 . NO - Replace the under-dash fuse/relay box (see «REMOVAL AND INSTALLATION»(/acura/rdx/i-2006-2009/remont/body-electrical/#under-dash-fuserelay-box__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.
23. Turn the ignition switch ON (II), and measure voltage between fuel pump control module 10P connector terminal No. 3 and body ground. 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»(/acura/rdx/i-2006-2009/remont/body-electrical/#under-dash-fuserelay-box__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.
28. Check for continuity between PCM connector terminal A15 and body ground. 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. Is there battery voltage? YES - Update the PCM if it does not have the latest software (see «PCM UPDATE»(/acura/rdx/i-2006-2009/remont/testing-diagnostics/#pgm-fi-system__pcm-update) ), or substitute a known-good PCM (see «SUBSTITUTING THE PCM»(/acura/rdx/i-2006-2009/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__substituting-the-pcm) ), then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM (see «PCM REPLACEMENT»(/acura/rdx/i-2006-2009/remont/testing-diagnostics/#pgm-fi-system__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. Is there battery voltage? YES - Go to step 85 . NO - If needed, replace the under-dash fuse/relay box (see «REMOVAL AND INSTALLATION»(/acura/rdx/i-2006-2009/remont/body-electrical/#under-dash-fuserelay-box__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»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system) ).
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. 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. 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.
50. Check for continuity between PCM connector terminal A38 and body ground. 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. 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»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system) ), 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»(/acura/rdx/i-2006-2009/remont/exteriorinterior-trim/#interior-trim__rear-door-sill-area) ).
57. Pull back the carpet to expose the access panel (see step 9 under «CARPET REPLACEMENT»(/acura/rdx/i-2006-2009/remont/exteriorinterior-trim/#interior-trim__carpet-replacement) ), then remove the access panel from the left side of the floor (see «FUEL TANK UNIT REMOVAL AND INSTALLATION»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system__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. 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»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system) ), 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»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system) ), 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»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system) ).
62. Check for continuity between fuel pump control module 10P connector terminal No. 5 and body ground. 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. 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. Is there battery voltage? YES - Go to step 68 . NO - Replace the fuel pump control module (see «FUEL PUMP CONTROL MODULE REPLACEMENT»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system) ), 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»(/acura/rdx/i-2006-2009/remont/exteriorinterior-trim/#interior-trim__rear-door-sill-area) ).
70. Pull back the carpet to expose the access panel (see step 9 under «CARPET REPLACEMENT»(/acura/rdx/i-2006-2009/remont/exteriorinterior-trim/#interior-trim__carpet-replacement) ), then remove the access panel from the left side of the floor (see «FUEL TANK UNIT REMOVAL AND INSTALLATION»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system__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»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system) ).
73. Connect fuel tank unit 4P connector terminal No. 2 to body ground with a jumper wire.
74. Check for continuity between fuel pump control module 10P connector terminal No. 6 and body ground. 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.
76. Check for continuity between fuel pump control module 10P connector terminal No. 7 and body ground. 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. Is there battery voltage? YES - Replace the fuel pump (see «FUEL PUMP/FUEL GAUGE SENDING UNIT REPLACEMENT»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system) ), then go to step 79 . NO - Substitute a known-good fuel pump control module (see «FUEL PUMP CONTROL MODULE REPLACEMENT»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system) ), 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»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system) ), 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»(/acura/rdx/i-2006-2009/remont/engine-control-systems/#idle-control-system__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»(/acura/rdx/i-2006-2009/remont/testing-diagnostics/#pgm-fi-system__pcm-update) ), or substitute a known-good PCM (see «SUBSTITUTING THE PCM»(/acura/rdx/i-2006-2009/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__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»(/acura/rdx/i-2006-2009/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__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»(/acura/rdx/i-2006-2009/remont/testing-diagnostics/#pgm-fi-system__pcm-replacement) ). If any other Temporary DTCs or DTCs are indicated, go to the indicated DTCs troubleshooting.

Fuel Pressure Relieving

Note. Before doing this procedure, make sure the engine is cold. Before disconnecting fuel lines or hoses, relieve pressure from the system by disabling the fuel pump and then disconnecting the fuel tube/quick connect fitting in the engine compartment.

Scheme 40

Scheme 41

Scheme 42

Scheme 43

1. Make sure you have the anti-theft codes for the audio system and the navigation system (if equipped).
2. Turn the ignition switch OFF.
3. Connect the HDS to the data link connector (DLC) (A) located under the driver's side of the dashboard.
4. Turn the ignition switch to LOCK (0).
5. Remove the fuel fill cap to relieve the pressure in the fuel tank.
6. Turn the ignition switch to ON (II).
7. From the INSPECTION MENU of the HDS, select: Fuel Pump OFF, then start the engine, and let it idle until it stalls. NOTE: Do not allow the engine to idle above 1,000 RPM or the PCM will continue to operate the fuel pump. A DTC or a Temporary DTC may be set during this procedure. Check for DTCs, and clear them as needed (see «HDS CLEAR COMMAND»(/acura/rdx/i-2006-2009/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__hds-clear-command) ).
8. Turn the ignition switch to LOCK (0).
9. Do the battery terminal disconnection procedure (see «DISCONNECTION»(/acura/rdx/i-2006-2009/remont/body-electrical/#battery__disconnection) ).
10. Remove the quick-connect fitting cover (A).
11. Check the fuel quick-connect fitting for dirt, and clean it if needed.
12. Place a rag or shop towel over the quick-connect fitting (A).
13. Disconnect the quick-connect fitting (A): Hold the connector (B) with one hand, and squeeze the retainer tabs (C) with the other hand to release them from the locking tabs (D). Pull the connector off. NOTE: Be careful not to damage the line (E) or other parts. Do not use tools. If the connector does not move, keep the retainer tabs pressed down, and alternately pull and push the connector until it comes off easily. Do not remove the retainer from the line; once removed, the retainer must be replaced with a new one.
14. After disconnecting the quick-connect fitting, check it for dirt or damage (see step 5 ).
15. Do the battery terminal reconnection procedure (see «RECONNECTION»(/acura/rdx/i-2006-2009/remont/body-electrical/#battery__reconnection) ).

Scheme 44

Scheme 45

Scheme 46

Scheme 47

1. Remove the driver's dashboard under cover (see «DRIVER'S DASHBOARD UNDERCOVER REMOVAL/INSTALLATION»(/acura/rdx/i-2006-2009/remont/gauges-instrument-panels/#dashboard-instrument-panel__drivers-dashboard-undercover-removalinstallation) ).
2. Remove PGM-FI main relay 2 (FUEL PUMP) (A) from the under-dash fuse/relay box.
3. Start the engine, and let it idle until it stalls. NOTE: If any DTCs are stored, clear and ignore them.
4. Turn the ignition switch OFF.
5. Remove the fuel fill cap to relieve the pressure in the fuel tank.
6. Do the battery terminal disconnection procedure (see «DISCONNECTION»(/acura/rdx/i-2006-2009/remont/body-electrical/#battery__disconnection) ).
7. Remove the quick-connect fitting cover (A).
8. Check the fuel quick-connect fitting for dirt, and clean it if needed.
9. Place a rag or shop towel over the quick-connect fitting (A).
10. Disconnect the quick-connect fitting (A): Hold the connector (B) with one hand, and squeeze the retainer tabs (C) with the other hand to release them from the locking tabs (D). Pull the connector off. NOTE: Be careful not to damage the line (E) or other parts. Do not use tools. If the connector does not move, keep the retainer tabs pressed down, and alternately pull and push the connector until it comes off easily. Do not remove the retainer from the line; once removed, the retainer must be replaced with a new one.
11. After disconnecting the quick-connect fitting, check it for dirt or damage (see step 5 ).
12. Do the battery reconnection procedure (see «RECONNECTION»(/acura/rdx/i-2006-2009/remont/body-electrical/#battery__reconnection) ).

Fuel Pressure Test

Special Tools Required

1. Fuel pressure gauge 07406-004000B
2. Fuel pressure gauge attachment set 07AAJ-S6MA150

Scheme 48

Scheme 49

1. Relieve the fuel pressure (see «FUEL PRESSURE RELIEVING»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system__fuel-pressure-relieving) ).
2. Disconnect the vacuum hose (A) from the fuel pressure regulator (B), and pinch it closed with a clamp (C).
3. Disconnect the quick-connect fitting. Attach the fuel pressure gauge attachment set and the fuel pressure gauge.
4. Reinstall the intake airduct (airflow tube) (see step 16 under «INSTALLATION»(/acura/rdx/i-2006-2009/remont/exhaust/#intake-manifold-and-exhaust-system) ).
5. Start the engine, and let it idle. If the engine starts, go to step 7 . If the engine does not run, go to step 6 .
6. Check to see if the fuel pump is running: Listen to the fuel filler port with the fuel fill cap removed. The fuel pump should run for 2 seconds when the ignition switch is first turned on. If the pump runs, go to step 7 . If the pump does not run, refer to the «DTC TROUBLESHOOTING»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system) .
7. Read the fuel pressure gauge. The pressure should be 320-370 kPa (3.3-3.8 kgf/cm 2 , 47-54 psi).
8. With the engine running, unpinch and reconnect the vacuum hose while you watch the pressure gauge. The pressure should fall when you connected the hose.

1. If the pressure falls, and the fuel pressure was OK in step 7, the test is complete.
2. If the pressure did not fall, check the vacuum line between the pressure regulator and the intake manifold. If the line is OK, replace the fuel pressure regulator (see «FUEL PRESSURE REGULATOR REPLACEMENT»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system) ).
3. If the pressure falls, but the fuel pressure was lower than specified in step 7, check for a clogged fuel filter (see «FUEL PUMP/FUEL GAUGE SENDING UNIT REPLACEMENT»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system) ), and for leaks in the fuel lines (see «FUEL LINE INSPECTION»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system__fuel-line-inspection) ).
4. If the pressure falls, but the fuel pressure was higher than specified in step 7, check for a pinched or clogged fuel return hose or line (see «FUEL LINE INSPECTION»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system__fuel-line-inspection) ).

Transfer Fuel Pump Test

Special Tools Required

Vacuum pump/gauge, 0-30 in.Hg, Snap-on YA4000A or equivalent, commercially available

Scheme 50

Scheme 51

Scheme 52

1. Remove the secondary fuel gauge sending unit (see «SECONDARY FUEL GAUGE SENDING UNIT REMOVAL/INSTALLATION»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system__secondary-fuel-gauge-sending-unit-removalinstallation) ).
2. Connect the vacuum pump/gauge 0-30 in.Hg to the transfer tube (A).
3. Turn the ignition switch ON (II).
4. From the INSPECTION MENU of the HDS, select Fuel Pump ON.
5. Read the vacuum pump/gauge 0-30 in.Hg. The vacuum should be 4.0 kPa (1.2 in.Hg, 30 mmHg). If the vacuum is OK, the transfer fuel pump and transfer tube is OK. If the vacuum is out of specification, go to step 6 .
6. Turn the ignition switch OFF.
7. Install the secondary fuel gauge sending unit (see «INSTALLATION»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system) ).
8. Remove the fuel tank unit (see «FUEL TANK UNIT REMOVAL AND INSTALLATION»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system__fuel-tank-unit-removal-and-installation) ).
9. Connect the vacuum pump/gauge 0-30 in.Hg to the fuel tank unit.
10. Lower the fuel tank unit (A) into the fuel tank until the pick up screen is submerged in the fuel.
11. Connect the fuel tank unit 4P connector.
12. Turn the ignition switch ON (II).
13. From INSPECTION MENU of the HDS, select Fuel Pump ON.
14. Read the vacuum pump/gauge 0-30 in.Hg. The vacuum should be 4.0 kPa (1.2 in.Hg, 30 mmHg).

1. If the vacuum is OK, replace the transfer tube, then recheck the fuel vacuum.
2. If the vacuum is out of specification, replace the fuel tank unit (see «FUEL TANK UNIT REMOVAL AND INSTALLATION»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system__fuel-tank-unit-removal-and-installation) ), then recheck the fuel vacuum.

Fuel Tank Draining

1. Remove the fuel tank unit (see «FUEL TANK UNIT REMOVAL AND INSTALLATION»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system__fuel-tank-unit-removal-and-installation) ).
2. Using a hand pump, a hose, and a container suitable for fuel, draw the fuel from the fuel tank.
3. Reinstall the fuel tank unit (see «INSTALLATION»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system) ).

Fuel Line Inspection

Check the fuel system lines and hoses for damage, leaks, and deterioration. Replace any damaged parts.

Scheme 53

Check all clamps, and retighten any if needed.

Scheme 54

Fuel Line/Quick-Connect Fitting Precautions

The fuel line/quick-connect fittings (A), (B), (C), (D), (E), and (F) connect the fuel rail (G) to the fuel feed hose (H), the fuel feed hose to the fuel pressure regulator base (I), the fuel pressure regulator base to the fuel feed line (J), the fuel feed line (K) and fuel return line (L) to the fuel tank unit (M), the fuel vapor line (O) to the EVAP canister (P), and the fuel tank vapor recirculation tube (Q) to the fuel fill pipe (F).

When removing or installing the fuel feed hose, fuel pressure regulator base, fuel vapor line, fuel tank unit, fuel tank, EVAP canister, or fuel fill pipe, it is necessary to disconnect or connect the quick-connect fittings. Pay attention to the following

1. The fuel feed hoses, fuel line, and quick-connect fittings are not heat-resistant; be careful not to damage them during welding or other heat-generating procedures.
2. The fuel feed hoses, fuel line, and quick-connect fittings are not acid-proof; do not touch them with a shop towel that was used for wiping battery electrolyte. Replace them if they come in contact with electrolyte or something similar.
3. When connecting or disconnecting the fuel feed hoses, fuel line, and quick-connect fittings, be careful not to bend or twist them excessively. Replace them if they are damaged.

Scheme 55

Scheme 56

A disconnected quick-connect fitting can be reconnected, but the retainer on the mating line cannot be reused once it has been removed from the line. Replace the retainer when

1. replacing the fuel rail.
2. replacing the fuel line.
3. replacing the fuel return line.
4. replacing the fuel pump.
5. replacing the fuel filter.
6. replacing the fuel gauge sending unit.
7. replacing the EVAP purge line.
8. replacing the EVAP canister.
9. replacing the fuel tank.
10. replacing the fuel fill pipe.
11. it has been removed from the line.
12. it is damaged.

LINE DIAMETER AND RETAINER COLOR CHART

Fuel Line/Quick-Connect Fitting Removal

Note. Before you work on the fuel lines and fittings, read the "Fuel Line/Quick-Connect Fitting Precautions" (see FUEL LINE/QUICK-CONNECT FITTING PRECAUTIONS ).

Scheme 57

Scheme 58

Scheme 59

Scheme 60

Scheme 61

1. If equipped, remove the quick-connect fitting cover from the fuel line. Raise the cover (A) from the fuel line (B), and remove it as shown.
2. Relieve the fuel pressure (see «FUEL PRESSURE RELIEVING»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system__fuel-pressure-relieving) ).
3. Check the fuel quick-connect fittings (A) for dirt, and clean them if needed.
4. Place a rag or shop towel over the quick-connect fitting. Hold the connector (A) with one hand, and squeeze the retainer tabs (B) with the other hand to release them from the locking tabs (C). Pull the connector off. NOTE: Be careful not to damage the line (D) or other parts. Do not use tools. If the connector does not move, keep the retainer tabs pressed down, and alternately pull and push the connector until it comes off easily. Do not remove the retainer from the line; once removed, the retainer must be replaced with a new one.
5. Check the contact area (A) of the line (B) for dirt or damage. If dirty, clean the connector with a pressure washer, and dry it with the compressed air. If it is rusty or damaged, replace the fuel filter, or fuel feed line.
6. To prevent damage and keep foreign matter out, cover the disconnected connector and line ends with plastic bags (A).

Note. The retainer cannot be reused once it has been removed from the line. Replace the retainer when

1. replacing the fuel rail.
2. replacing the fuel feed line.
3. replacing the fuel return line.
4. replacing the fuel pump.
5. replacing the fuel filter.
6. replacing the fuel gauge sending unit.
7. replacing the EVAP purge pipe.
8. replacing the EVAP canister.
9. replacing the fuel tank.
10. replacing the fuel fill pipe.
11. it has been removed from the line.
12. it is damaged.

Scheme 62

Fuel Line/Quick-Connect Fitting Installation

Note. Before you work on the fuel lines and fittings, read the "Fuel Line/Quick-Connect Fitting Precautions" (see FUEL LINE/QUICK-CONNECT FITTING PRECAUTIONS ).

Scheme 63

Scheme 64

Scheme 65

Scheme 66

Scheme 67

Scheme 68

Scheme 69

Scheme 70

Scheme 71

1. Check the contact area (A) of the line (B) for dirt or damage, and clean it if needed.
2. Insert a new retainer (A) into the connector (B) if the retainer is damaged, or after: replacing the fuel rail. replacing the fuel feed line. replacing the fuel return line. replacing the fuel pump. replacing the fuel filter. replacing the fuel gauge sending unit. replacing the EVAP purge pipe. replacing the EVAP canister. replacing the fuel tank. replacing the fuel fill pipe. removing the retainer from the line. Use the same manufacturer retainer and the same size retainer when the replacing the retainer (see «FUEL LINE/QUICK-CONNECT FITTING PRECAUTIONS»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system__fuel-linequick-connect-fitting-precautions) ).
3. Before connecting a new fuel tube/quick-connect fitting assembly (A), remove the old retainer from the mating line.
4. Align the quick-connect fittings with the line (A), and align the retainer locking tabs (B) with the connector grooves (C). Then press the quick-connect fittings onto the line until both retainer tabs lock with a clicking sound. NOTE: If it is hard to connect, put a small amount of new engine oil on the line end. Connection with new retainer Reconnection to existing retainer Connection to new fuel line
5. When you reconnect the connector with the old retainer, make sure the connection is secure and the tabs are firmly locked into place; check visually and also by pulling the connector. When you replace the fuel line with a new one, make sure you remove the ring pull upwards after you confirm the connection is secure. NOTE: Before you remove the ring pull, make sure the fuel line connection is secure. If the connection is not secure, the ring pull could break when you try to remove it. Reconnection to existing retainer Connection to new fuel line
6. Reconnect the negative cable to the battery, and turn the ignition switch ON (II) (but do not operate the starter motor). The fuel pump will run for about 2 seconds, and fuel pressure will rise. Repeat this two or three times, and check that there is no leakage in the fuel supply system.
7. If equipped, install the guick-connect fitting cover. Set the groove of the cover (A) on the fuel line (B) as shown, then install it. Make sure the cover is firmly locked in place.

Scheme 72

1. Relieve the fuel pressure (see «FUEL PRESSURE RELIEVING»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system__fuel-pressure-relieving) ).
2. Remove the charge air cooler (see «CHARGE AIR COOLER REMOVAL AND INSTALLATION»(/acura/rdx/i-2006-2009/remont/exhaust/#intake-manifold-and-exhaust-system) ).
3. Remove the injector cover (see step 3 ).
4. Disconnect the connectors from the injectors, then. Remove the harness holder (see step 4 ).
5. Remove the fuel pulsation damper (A) from the fuel rail (B).
6. Install the parts in the reverse order of removal with a new sealing washer (C).

Scheme 73

Scheme 74

Scheme 75

1. Relieve the fuel pressure (see «FUEL PRESSURE RELIEVING»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system__fuel-pressure-relieving) ).
2. Remove the charge air cooler (see «CHARGE AIR COOLER REMOVAL AND INSTALLATION»(/acura/rdx/i-2006-2009/remont/exhaust/#intake-manifold-and-exhaust-system) ).
3. Remove the pressure regulator cover (A).
4. Disconnect the fuel return hose (B), and vacuum hose (C).
5. Loosen the nut (A), then remove the fuel pressure regulator (B).
6. Coat the new O-ring (C) with clean engine oil, and install the fuel pressure regulator into the fuel pressure regulator base (D) by hand until the washer (E) is pressed between the base and the regulator. NOTE: Do not fully tighten the fuel pressure regulator yet.
7. Make sure the fuel return pipe (A) is positioned as shown. If needed, turn the fuel pressure regulator counterclockwise to line up the pipe. NOTE: Do not turn the fuel pressure regulator clockwise. Do not turn the fuel pressure regulator counterclockwise more than once complete turn.
8. Tighten the nut (B) to the specified torque.
9. Connect the fuel return hose and vacuum hose.
10. Turn the ignition switch ON (II), but do not operate the starter. After fuel pump runs for about 2 seconds, the fuel rail is pressurized. Repeat this two or three times, then check for leaks.
11. Install the pressure regulator cover, then install the charge air cooler (see «INSTALLATION»(/acura/rdx/i-2006-2009/remont/exhaust/#intake-manifold-and-exhaust-system) ).

Scheme 76

Scheme 77

1. Remove the fuel pressure regulator (see «FUEL PRESSURE REGULATOR REPLACEMENT»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system) ).
2. Remove the bolt (A) and nut (B), then remove the fuel pipe protector (C).
3. Remove the quick-connect fitting covers (D).
4. Disconnect the quick-connect fittings (A).
5. Remove the pressure regulator base (B).
6. Reinstall the parts in the reverse order of removal.

Fuel Tank Unit Removal and Installation

Special Tools Required

Fuel sender wrench 07AAA-S0XA100

Scheme 78

Scheme 79

Scheme 80

1. Relieve the fuel pressure (see «FUEL PRESSURE RELIEVING»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system__fuel-pressure-relieving) ).
2. Remove the fuel fill cap.
3. Fold the rear seat down, then remove the left rear door sill trim (see «REAR DOOR SILL AREA»(/acura/rdx/i-2006-2009/remont/exteriorinterior-trim/#interior-trim__rear-door-sill-area) ).
4. Pull back the carpet to expose the access panel (see step 9 under «CARPET REPLACEMENT»(/acura/rdx/i-2006-2009/remont/exteriorinterior-trim/#interior-trim__carpet-replacement) ).
5. Remove the access panel (A) from the left side of the floor.
6. Disconnect the fuel tank unit 4P connector (B).
7. Disconnect the quick-connect fittings (C) from the fuel tank unit.
8. Using the special tool, loosen the locknut (A).
9. Remove the locknut (A), and lift up the fuel tank unit (B) from the fuel tank. Then disconnect the transfer tube (C).

Scheme 81

Scheme 82

Scheme 83

1. Temporarily attach a new base gasket (A) to the fuel tank unit (B), position the mark of the transfer tube (C) up, connect the transfer tube (D), then insert the fuel tank unit partially into the fuel tank. NOTE: Be careful not to damage the new base gasket. Be careful not to bend the fuel gauge sending unit. Do not coat the base gasket with oil.
2. Transfer the base gasket (A) from the fuel tank unit to the fuel tank.
3. Align the marks (B) on the fuel tank and the fuel tank unit, then insert the fuel tank unit until it sits on the base gasket. NOTE: To prevent a fuel leak, check the base gasket, visually or by hand, to make sure it is not pinched.
4. Using the tool, tighten a new locknut (A) with a new locknut plate (B) to the specified torque. NOTE: After tightening, make sure the marks are still aligned. After installation, check the base gasket visually or by hand to be sure it is not pinched.
5. Connect the fuel tank unit 4P connector.
6. Reconnect the negative cable to the battery, and turn the ignition switch ON (II) (but do not operate the starter motor). The fuel pump will run for about 2 seconds, and fuel pressure will rise. Repeat two or three times, and check that there is no leakage in the fuel supply system.
7. Install the parts in the reverse order of removal.

Fuel Filter Replacement

The fuel filter should be replaced whenever the fuel pressure drops below the specified value (see FUEL PRESSURE TEST ), after making sure that the fuel pump and the fuel pressure regulator are OK.

Scheme 84

1. Remove the fuel tank unit (see «FUEL TANK UNIT REMOVAL AND INSTALLATION»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system__fuel-tank-unit-removal-and-installation) ).
2. Remove the fuel strainer set (A).
3. Check these items before installing the fuel tank unit: When connecting the wire harness, make sure the connection is secure and the connectors (B) are firmly locked into place. When installing the fuel gauge sending unit (C), make sure the connection is secure and the connector is firmly locked into place. Be careful not to bend or twist it excessively.
4. Install the parts in the reverse order of removal with new O-rings (D). NOTE: Coat the O-rings with clean engine oil.
5. Install the fuel tank unit (see «INSTALLATION»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system) ).

Scheme 85

1. Remove the fuel tank unit (see «FUEL TANK UNIT REMOVAL AND INSTALLATION»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system__fuel-tank-unit-removal-and-installation) ).
2. Remove the fuel level sensor (fuel gauge sending unit) (A) from the fuel tank unit (B).
3. Check these items before installing the fuel tank unit: When connecting the wire harness, make sure the connection is secure and the connector (C) is firmly locked into place. When installing the fuel gauge sending unit, make sure the connection is secure and the connector is firmly locked into place. Be careful not to bend or twist it excessively.
4. Install the parts in the reverse order of removal
5. Install the fuel tank unit (see «INSTALLATION»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system) ).

Secondary Fuel Gauge Sending Unit Removal/Installation

Special Tools Required

Fuel sender wrench 07AAA-S0XA100

Scheme 86

Scheme 87

1. Relieve the fuel pressure (see «FUEL PRESSURE RELIEVING»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system__fuel-pressure-relieving) ).
2. Remove the fuel fill cap.
3. Fold the rear seat down, then remove the right rear door sill trim (see «REAR DOOR SILL AREA»(/acura/rdx/i-2006-2009/remont/exteriorinterior-trim/#interior-trim__rear-door-sill-area) ).
4. Pull back the carpet to expose the access panel (see step 9 under «CARPET REPLACEMENT»(/acura/rdx/i-2006-2009/remont/exteriorinterior-trim/#interior-trim__carpet-replacement) ).
5. Remove the access panel (A) from the right side of the floor.
6. Disconnect the secondary fuel gauge sending unit 4P connector (B).
7. Using the special tool, loosen the locknut (A).
8. Remove the locknut (A), and lift up the secondary fuel gauge sending unit (B) from the fuel tank. Then disconnect the transfer tube (C).

Scheme 88

Scheme 89

Scheme 90

Scheme 91

1. Temporarily attach a new base gasket (A) to the secondary fuel gauge sending unit (B), position the mark on the transfer tube (C) up, the transfer tube (D), then insert the secondary fuel gauge sending unit partially into the fuel tank. NOTE: Be careful not to damage the new base gasket. Be careful not to bend the secondary fuel gauge sending unit. Do not coat the base gasket with oil.
2. Transfer the base gasket (A) from the secondary fuel gauge sending unit to the fuel tank.
3. Align the marks (B) on the fuel tank and the secondary fuel gauge sending unit, then insert the secondary fuel gauge sending unit and allow it to contact the base gasket. NOTE: To avoid a fuel leak, check the base gasket, visually or by hand, to make sure it is not pinched.
4. Using the tool, tighten a new locknut (A) with the new locknut plate (B) to the specified torque. NOTE: After tightening, make sure the marks are still aligned. After installation, check the base gasket visually or by hand to be sure it is not pinched.
5. Connect the secondary fuel gauge sending unit 4P connector.
6. Reconnect the negative cable to the battery, and turn the ignition switch ON (II) (but do not operate the starter motor). The fuel pump will run for about 2 seconds, and fuel pressure will rise. Repeat two or three times, and check that there is no leakage in the fuel supply system.
7. Install the parts in the reverse order of removal.

Scheme 92

Scheme 93

Scheme 94

Scheme 95

1. Drain the fuel tank (see «FUEL TANK DRAINING»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system__fuel-tank-draining) ).
2. Reinstall the fuel tank unit without connecting quick-connect fittings and fuel tank unit 4P connector.
3. Disconnect the secondary fuel gauge sending unit 4P connector (see step 5 ).
4. Remove the fuel fill pipe cover (A).
5. Disconnect the quick-connect fitting (B).
6. Lift the vehicle, and support it with jack stands.
7. Disconnect the fuel fill tube (A) from the fuel tank. Slide back the clamp, then twist the tube as you pull to avoid damage it.
8. Disconnect the fuel vent tube (A).
9. Remove the exhaust pipe (see «EXHAUST PIPE AND MUFFLER REPLACEMENT»(/acura/rdx/i-2006-2009/remont/exhaust/#intake-manifold-and-exhaust-system__exhaust-pipe-and-muffler-replacement) ).
10. Remove the propeller shaft (see «PROPELLER SHAFT REMOVAL»(/acura/rdx/i-2006-2009/remont/axle-shafts/#drivelineaxle) ).
11. Remove the fuel tank cover (A).
12. Place a jack or support under the fuel tank (B).
13. Remove the strap bolts and straps (C).
14. Remove the fuel tank.
15. Install the parts in the reverse order of removal.

Scheme 96

Scheme 97

Scheme 98

1. Drain the fuel tank (see «FUEL TANK DRAINING»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system__fuel-tank-draining) ).
2. Remove the fuel fill cap.
3. Disconnect the fuel fill tube (A) from the fuel tank. Slide back the clamp, then twist the tube as you pull to avoid damaging it.
4. Remove the fuel fill pipe cover (A).
5. Disconnect the quick-connect fitting (B).
6. Remove the bolts (A), then remove the fuel fill pipe (B) and fuel fill tube (C).
7. Install the parts in the reverse order of removal.

Scheme 99

1. Fold the rear seat down, then remove the rear seat side bolster (see «SEAT SIDE BOLSTER»(/acura/rdx/i-2006-2009/remont/seats/#seats__seat-side-bolster) ).
2. Disconnect the fuel pump control module connector (A).
3. Remove the fuel pump control module (B).
4. Install the parts in the reverse order of removal.

Fuel Gauge Sending Unit Test

Note. For the fuel gauge system circuit diagram, refer to the Gauges Circuit Diagram (see CIRCUIT DIAGRAM ).

Scheme 100

Scheme 101

1. Check the No. 10 METER (7.5 A) fuse in the under-dash fuse/relay box before testing.
2. Check for body electrical system DTCs. If no problem is found, go to step 3 . If DTC B1175 or B1176 is indicated, go to the indicated DTCs troubleshooting.
3. Turn the ignition switch OFF.
4. Fold the rear seat down, then remove the left rear door sill trim (see «REAR DOOR SILL AREA»(/acura/rdx/i-2006-2009/remont/exteriorinterior-trim/#interior-trim__rear-door-sill-area) ).
5. Pull back the carpet to expose the access panel (see step 9 under «CARPET REPLACEMENT»(/acura/rdx/i-2006-2009/remont/exteriorinterior-trim/#interior-trim__carpet-replacement) ).
6. Remove the access panel (A) from the left side of the floor.
7. Disconnect the fuel tank unit 4P connector (B).
8. Remove the fuel tank unit from the fuel tank (see «FUEL TANK UNIT REMOVAL AND INSTALLATION»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system__fuel-tank-unit-removal-and-installation) ). NOTE: If the fuel tank is full, drain the fuel (see «FUEL TANK DRAINING»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system__fuel-tank-draining) ).
9. Measure resistance between the No. 1 and No. 3 terminals of the fuel tank unit 4P connector with the float at E (EMPTY), LOW (LOW FUEL INDICATOR), and F (FULL) positions. If you do not get the following readings, replace the fuel gauge sending unit (see «FUEL PUMP/FUEL GAUGE SENDING UNIT REPLACEMENT»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system) ). If the fuel gauge sending unit test is OK, do the secondary fuel gauge sending unit test (see «SECONDARY FUEL GAUGE SENDING UNIT TEST»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system) ). FLOAT POSITION CHART Float Position F 5.7 in. (144.0 mm) LOW 3.7 in. (93.7 mm) E 2.2 in. (54.8 mm) Resistance (ohms) 18 to 22 703.6 to 743 772 to 788 NOTE: Remove the No. 23 BACK UP (10 A) fuse from the under-hood fuse/relay box for at least 30 seconds after completing troubleshooting, otherwise it may take up to 20 minutes for the fuel gauge to indicate the correct fuel level.

Scheme 102

1. Fold the rear seat down, then remove the right rear door sill trim (see «REAR DOOR SILL AREA»(/acura/rdx/i-2006-2009/remont/exteriorinterior-trim/#interior-trim__rear-door-sill-area) ).
2. Pull back the carpet to expose the access panel (see step 9 under «CARPET REPLACEMENT»(/acura/rdx/i-2006-2009/remont/exteriorinterior-trim/#interior-trim__carpet-replacement) ).
3. Remove the access panel (A) from the right side of the floor.
4. Disconnect the secondary fuel gauge sending unit 4P connector (B).
5. Remove the secondary fuel gauge sending unit from the fuel tank (see «SECONDARY FUEL GAUGE SENDING UNIT REMOVAL/INSTALLATION»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system__secondary-fuel-gauge-sending-unit-removalinstallation) ).
6. Measure resistance between the No. 1 and No. 3 terminals of the secondary fuel gauge sending unit 4P connector with the float at E (EMPTY), 1/2 (HALF FULL), and F (FULL) positions.

FLOAT POSITION CHART

Note. Remove the No. 23 BACK UP (10 A) fuse from the under-hood fuse/relay box for at least 10 seconds after completing troubleshooting, otherwise it may take up to 20 minutes for the fuel gauge to indicate the correct fuel level.

Scheme 103

Low Fuel Indicator Test

1. Do the gauge self-diagnostic test (see «SELF-DIAGNOSTIC FUNCTION»(/acura/rdx/i-2006-2009/remont/gauges-instrument-panels/#gauges__self-diagnostic-function) ). If the low fuel indicator flashes, go to step 2 . If the low fuel indicator does not flash, replace the gauge control module (see «GAUGE CONTROL MODULE REPLACEMENT»(/acura/rdx/i-2006-2009/remont/gauges-instrument-panels/#gauges__gauge-control-module-replacement) ).
2. Check for body electrical system DTCs. If any DTCs are indicated, do the indicated DTCs troubleshooting. If no DTCs are indicated, go to step 3 .
3. Do the fuel gauge sending unit test (see «FUEL GAUGE SENDING UNIT TEST»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system__fuel-gauge-sending-unit-test) ), and secondary fuel gauge sending unit test (see «SECONDARY FUEL GAUGE SENDING UNIT TEST»(/acura/rdx/i-2006-2009/remont/fuel-system/#fuel-supply-system) )

See also:
• GENERAL TROUBLESHOOTING INFORMATION
• PCM IDLE LEARN PROCEDURE
• TRIM REMOVAL/INSTALLATION - REAR SIDE AREA
• CARPET REPLACEMENT
• REAR DOOR SILL AREA
• GAUGE CONTROL MODULE REPLACEMENT
• PCM UPDATE
• SUBSTITUTING THE PCM
• PCM REPLACEMENT
• DRIVER'S DASHBOARD UNDERCOVER REMOVAL/INSTALLATION
• POWER RELAY TEST
• REMOVAL AND INSTALLATION
• REMOVAL AND INSTALLATION
• HDS CLEAR COMMAND
• DISCONNECTION
• RECONNECTION
• INSTALLATION
• EXHAUST PIPE AND MUFFLER REPLACEMENT
• PROPELLER SHAFT REMOVAL
• SEAT SIDE BOLSTER
• CIRCUIT DIAGRAM
• SELF-DIAGNOSTIC FUNCTION
• FUEL GAUGE SENDING UNIT TEST
• FUEL PUMP/FUEL GAUGE SENDING UNIT REPLACEMENT
• SECONDARY FUEL GAUGE SENDING UNIT REMOVAL/INSTALLATION
• FUEL TANK UNIT REMOVAL AND INSTALLATION
• FUEL PRESSURE RELIEVING
• FUEL LINE INSPECTION
• FUEL LINE/QUICK-CONNECT FITTING PRECAUTIONS
• FUEL PRESSURE TEST
• FUEL TANK DRAINING