DTC Troubleshooting
DTC P2647: Rocker Arm Oil Pressure Switch Circuit High VoltageNOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information.
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 and the ECM/PCM.
NO - Go to step 5.
5. Check the result of step 4.
- Rocker arm oil pressure switch Failure
- Rocker arm oil pressure switch Open
- Rocker arm oil pressure switch SIG Line Open
- Rocker arm oil pressure switch GND Line Open
Is the test result any of the above?
YES - Go to step 6.
NO - Check for poor connections or loose terminals at the rocker arm oil pressure switch. If it is OK, replace the rocker arm oil control solenoid, then go to step 14.
6. Turn the ignition switch OFF.
7. Disconnect the rocker arm oil pressure switch 2P connector.
8. At the rocker arm oil pressure switch side, check for continuity between rocker arm oil pressure switch 2P connector terminals No. 1 and No. 2.
Is there continuity?
YES - Go to step 9.
NO - Replace the rocker arm oil pressure switch, then go to step 13.
9. Turn the ignition switch ON (II).
10. Measure voltage between rocker arm oil pressure switch 2P connector terminal No. 1 and body ground.
Is there battery voltage?
YES - Repair open in the wire between the rocker arm oil pressure switch and G101, then go to step 13.
NO - Go to step 11.
11. Measure voltage between ECM/PCM connector terminal A23 and body ground.
Is there battery voltage?
YES - Repair open in the wire between the ECM/PCM (A23) and the rocker arm 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 2P connector.
14. Turn the ignition switch ON (II).
15. Reset the ECM/PCM with the HDS.
16. Do the ECM/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 and the ECM/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.
NO - If the screen indicates FAILED, check for poor connections or loose terminals at the rocker arm oil pressure switch and the ECM/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 ECM/PCM if it does not have the latest software, or substitute a known-good ECM/PCM.
22. 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 and the ECM/PCM. If the ECM/PCM was updated, substitute a known-good ECM/PCM, then recheck. If the ECM/PCM was substituted, go to step 1.
NO - Go to step 23.
23. Monitor the OBD STATUS for DTC P2647 in the DTCs MENU with the HDS.
Does the screen indicate PASSED?
YES - If the ECM/PCM was updated, troubleshooting is complete. If the ECM/PCM was substituted, replace the original ECM/PCM. If any other Temporary DTCs or DTCs were indicated in step 22, 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 and the ECM/PCM. If the ECM/PCM was updated, substitute a known-good ECM/PCM, then recheck. If the ECM/PCM was substituted, go to step 1. If the screen indicates NOT COMPLETED, keep idling until a result comes on.