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Acura RL. Manual - part 672

Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES - Go to step 16.

NO - Repair open in the wire between the PCM (A7 (A6) *) and the A/F sensor (Sensor 1), then go to
step 23.

16. Remove the A/F sensor relay (LAF) (A).

Fig. 29: Identifying A/F Sensor Relay (LAF) (A)
Courtesy of AMERICAN HONDA MOTOR CO., INC.

17. Connect A/F sensor (Sensor 1)8P connector terminal No. 1 to body ground with a jumper wire.

Fig. 30: Connecting A/F Sensor (Sensor 1)8P Connector Terminal No. 1 To Body Ground With
Jumper Wire
Courtesy of AMERICAN HONDA MOTOR CO., INC.

18. Check for continuity between A/F sensor relay (LAF) 4P connector terminal No. 2 and body ground.

2007 Acura RL

2005-08 ENGINE PERFORMANCE PGM-FI System - RL

Friday, June 05, 2009 2:34:58 PM

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Fig. 31: Checking Continuity Between A/F Sensor Relay (LAF) 4P Connector Terminal No. 2
And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES - Go to step 19.

NO - Repair open in the wire between the A/F sensor (Sensor 1) and the A/F sensor relay (LAF), then
go to step 23.

19. Disconnect PCM connector E (31P).

20. Check for continuity between PCM connector terminal E4 and A/F sensor relay (LAF) 4P connector

terminal No. 4.

Fig. 32: Checking Continuity Between PCM Connector Terminal E4 And A/F Sensor Relay
(LAF) 4P Connector Terminal No. 4
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES - Go to step 21.

NO - Repair open in the wire between the PCM (E4) and the A/F sensor relay (LAF), then go to step
23.

21. Test the A/F sensor relay (LAF) (see POWER RELAY TEST ).

2007 Acura RL

2005-08 ENGINE PERFORMANCE PGM-FI System - RL

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Is the A/F sensor relay OK?

YES - Go to step 29.

NO - Replace the A/F sensor relay (LAF), then go to step 23.

22. Replace the A/F sensor (Sensor 1) (see A/F SENSOR REPLACEMENT ).

23. Reconnect all connectors.

24. Turn the ignition switch ON (II).

25. Reset the PCM with the HDS.

26. Do the PCM idle learn procedure (see PCM IDLE LEARN PROCEDURE ).

27. Check for Temporary DTCs or DTCs with the HDS.

Is DTC P0135 and/or P0155* indicated?

YES - Check for poor connections or loose terminals at the A/F sensor (Sensor 1), the A/F sensor
relay (LAF), the under-dash fuse/relay box, and the PCM, then go to step 1.

NO - Go to step 28.

28. Monitor the OBD STATUS for DTC P0135 and/or P01551 in the DTCs MENU with the HDS.

Does the screen indicate PASSED?

YES - Troubleshooting is complete. If any other Temporary DTCs or DTCs were indicated in step 27,
go to the indicated DTCs troubleshooting

29. Update the PCM if it does not have the latest software (see UPDATING THE PCM ), or substitute a

known-good PCM (see SUBSTITUTING THE PCM ).

30. Check for Temporary DTCs or DTCs with the HDS.

Is DTC P0135 and/or P0155* indicated?

YES - Check for poor connections or loose terminals at the A/F sensor (Sensor 1), the A/F sensor
relay (LAF), the under-dash fuse/relay box, 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 - Go to step 31.

31. Monitor the OBD STATUS for DTC P0135 and/or P0155* in the DTCs MENU with the HDS.

Does the screen indicate PASSED?

YES - If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the

2007 Acura RL

2005-08 ENGINE PERFORMANCE PGM-FI System - RL

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original PCM (see PCM REPLACEMENT ). If any other Temporary DTCs or DTCs were indicated
in step 30, go to the indicated DTCs troubleshooting

NO - If the screen indicates FAILED, check for poor connections or loose terminals at the A/F sensor
(Sensor 1), the A/F sensor relay (LAF), the under-dash fuse/relay box, 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. If the screen indicates NOT COMPLETED, keep idling until a
result comes on.

DTC P0137: REAR SECONDARY HO2S (BANK 1, SENSOR 2) CIRCUIT LOW VOLTAGE; DTC
P0157: FRONT SECONDARY HO2S (BANK 2, SENSOR 2) CIRCUIT LOW VOLTAGE

1. Turn the ignition switch ON (II).

2. Clear the DTC with the HDS.

3. Start the engine. Hold the engine speed at 3,000 RPM without load (in Park or neutral) until the

radiator fan comes on, then let it idle.

4. Check the HO2S S2 in the DATA LIST with the HDS.

Does the voltage stay at 0.29 V or less?

YES - Go to step 5.

NO - Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals
at the secondary HO2S (Sensor 2) and the PCM

5. Turn the ignition switch OFF.

6. Disconnect the secondary HO2S (Sensor 2) 4P connector.

7. Turn the ignition switch ON (II).

8. Check the HO2S S2 in the DATA LIST with the HDS.

Does the voltage stay at 0.29 V or less?

YES - Go to step 9.

NO - Go to step 13.

9. Turn the ignition switch OFF.

10. Jump the SCS line with the HDS.

11. Disconnect PCM connector B (24P).

12. Check for continuity between secondary HO2S (Sensor 2) 4P connector terminal No. 1 and body

ground.

NOTE:



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



Information marked with an asterisk (*) applies to the front bank (Bank
2).

2007 Acura RL

2005-08 ENGINE PERFORMANCE PGM-FI System - RL

Friday, June 05, 2009 2:34:58 PM

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