Acura RL. Manual - part 853

Does the screen indicate PASSED?  

YES -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 were indicated 
in step 28, go to the indicated DTCs troubleshooting. 

NO -If the screen indicates FAILED, check for poor connections or loose terminals at the rocker arm 
oil pressure switch (VTEC oil pressure switch) 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 P2647: ROCKER ARM OIL PRESSURE SWITCH (VTEC OIL PRESSURE SWITCH) 
CIRCUIT HIGH VOLTAGE 

1. Check the engine oil level. 

Is the engine oil level OK?  

YES -Go to step 2. 

NO -Adjust the engine oil to the proper level, then go to step 14. 

2. Turn the ignition switch ON (II).  

3. Clear the DTC with the HDS.  

4. Do the VTEC TEST in the INSPECTION MENU with the HDS. 

Is the result OK?  

YES -Intermittent failure, the system is OK at this time. Check for poor connections or loose 
terminals at the rocker arm oil pressure switch (VTEC oil pressure switch) and the PCM. 

NO -Go to step 5. 

5. Check the result of step 4. 



VTEC Switch Failure  



VTEC Switch Open  



VTEC Switch SIG Line Open  



VTEC Switch GND Line Open  

Is the test result one of the above?  

YES -Go to step 6. 

NO -Check for poor connections or loose terminals at the rocker arm oil pressure switch (VTEC oil 

NOTE:

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

 

2007 Acura RL 

2005-08 ENGINE PERFORMANCE VTEC - RL

  

me 

 

Friday, June 05, 2009 2:35:54 PM

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© 2005 Mitchell Repair Information Company, LLC. 

pressure switch). If it is OK, replace the rocker arm oil control solenoid (VTEC solenoid valve) (see 
ROCKER ARM OIL CONTROL SOLENOID (VTEC SOLENOID VALVE) 
REPLACEMENT ), then go to step 14. 

6. Turn the ignition switch OFF.  

7. Disconnect the rocker arm oil pressure switch (VTEC oil pressure switch) 2P connector.  

8. At the rocker arm oil pressure switch (VTEC oil pressure switch) side, check for continuity between 

rocker arm oil pressure switch (VTEC oil pressure switch) 2P connector terminals No. 1 and No. 2. 

Fig. 4: Checking Continuity Between Rocker Arm Oil Pressure Switch 2P Connector Terminals 
1 And 2 
Courtesy of AMERICAN HONDA MOTOR CO., INC. 

Is there continuity?  

YES -Go to step 9. 

NO -Replace the rocker arm oil pressure switch (VTEC oil pressure switch) (see ROCKER ARM 
OIL PRESSURE SWITCH (VTEC OIL PRESSURE SWITCH) 
REMOVAL/INSTALLATION ), then go to step 13. 

9. Turn the ignition switch ON (II).  

10. Measure voltage between rocker arm oil pressure switch (VTEC oil pressure switch) 2P connector 

terminal No. 1 and body ground. 

Fig. 5: Measuring Voltage Between Rocker Arm Oil Pressure Switch 2P Connector Terminal 1 
And Body Ground 
Courtesy of AMERICAN HONDA MOTOR CO., INC.

 

2007 Acura RL 

2005-08 ENGINE PERFORMANCE VTEC - RL

  

me 

 

Friday, June 05, 2009 2:35:54 PM

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© 2005 Mitchell Repair Information Company, LLC. 

Is there battery voltage?  

YES -Repair open in the wire between the rocker arm oil pressure switch (VTEC oil pressure switch) 
and G101, then go to step 13. 

NO -Go to step 11. 

11. Measure voltage between PCM connector terminal A23 and body ground. 

Fig. 6: Measuring Voltage Between PCM Connector Terminal A23 And Body Ground 
Courtesy of AMERICAN HONDA MOTOR CO., INC. 

Is there battery voltage?  

YES -Repair open in the wire between the PCM (A23) and the rocker arm oil pressure switch (VTEC 
oil pressure switch), then go to step 12. 

NO -Go to step 19. 

12. Turn the ignition switch OFF.  

13. Reconnect the rocker arm oil pressure switch (VTEC oil pressure switch) 2P connector.  

14. Turn the ignition switch ON (II).  

15. Reset the PCM with the HDS.  

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

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

Is DTC P2647 indicated?  

YES -Check for poor connections or loose terminals at the rocker arm oil pressure switch (VTEC oil 
pressure switch) and the PCM, then go to step 1. 

NO -Go to step 18. 

18. Monitor the OBD STATUS for DTC P2647 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 17, 
go to the indicated DTCs troubleshooting.

 

2007 Acura RL 

2005-08 ENGINE PERFORMANCE VTEC - RL

  

me 

 

Friday, June 05, 2009 2:35:54 PM

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© 2005 Mitchell Repair Information Company, LLC. 

NO -If the screen indicates FAILED, check for poor connections or loose terminals at the rocker arm 
oil pressure switch (VTEC oil pressure switch) and the PCM, then go to step 1. If the screen indicates 
NOT COMPLETED, keep idling until a result comes on. 

19. Turn the ignition switch OFF.  

20. Reconnect all connectors.  

21. 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 ).  

22. Do the VTEC TEST in the INSPECTION MENU with the HDS.  

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

Is DTC P2647 indicated?  

YES -Check for poor connections or loose terminals at the rocker arm oil pressure switch (VTEC oil 
pressure switch) 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 24. 

24. Monitor the OBD STATUS for DTC P2647 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 
original PCM (see PCM REPLACEMENT ). If any other Temporary DTCs or DTCs were indicated 
in step 23, go to the indicated DTCs troubleshooting. 

NO -If the screen indicates FAILED, check for poor connections or loose terminals at the rocker arm 
oil pressure switch (VTEC oil pressure switch) 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 P2648: ROCKER ARM OIL CONTROL SOLENOID (VTEC SOLENOID VALVE) CIRCUIT 
LOW VOLTAGE 

1. Turn the ignition switch ON (II).  

2. Clear the DTC with the HDS.  

3. Do the VTEC TEST in the INSPECTION MENU with the HDS. 

Is the result OK?  

YES -Intermittent failure, the system is OK at this time. Check for poor connections or loose 
terminals at the rocker arm oil control solenoid (VTEC solenoid valve) and the PCM. 

NOTE:

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

 

2007 Acura RL 

2005-08 ENGINE PERFORMANCE VTEC - RL

  

me 

 

Friday, June 05, 2009 2:35:54 PM

Page 8 

© 2005 Mitchell Repair Information Company, LLC.