DTC Troubleshooting
DTC Troubleshooting: P2647
DTC P2647:
Rocker Arm Oil Pressure Switch Circuit High Voltage
NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information Initial Inspection and Diagnostic Overview.
1. Check the engine oil level.
Is the engine oil level OK?
YES -
Go to step 2.
NO -
Adjust the engine oil level, then go to step 17.
2. Turn the ignition switch to ON (II).
3. Clear the DTC with the HDS.
4. Check the rocker arm oil pressure switch in the DATA LIST with the HDS.
Does the screen indicate OFF?
YES -
Go to step 5.
NO -
Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the rocker arm oil pressure switch, the rocker arm oil control solenoid, and the PCM.�
5. Turn the ignition switch to LOCK (0).
6. Disconnect the rocker arm oil pressure switch 2P connector.
7. Connect rocker arm oil pressure switch 2P connector terminals No. 1 and No. 2 with a jumper wire.
8. Turn the ignition switch to ON (II).
9. Check the rocker arm oil pressure switch in the DATA LIST with the HDS.
Does the screen indicate ON?
YES -
Replace the rocker arm oil pressure switch Service and Repair, then go to step 16.
NO -
Go to step 10.
10. Turn the ignition switch to LOCK (0).
11. Remove the jumper wire from the rocker arm oil pressure switch.
12. Jump the SCS line with the HDS.
13. Disconnect PCM connector B (49P).
14. Check for continuity between PCM connector terminal B20 and rocker arm oil pressure switch 2P connector terminal No. 1.
Is there continuity?
YES -
Go to step 15.
NO -
Repair open in the wire between the PCM(B20) and the rocker arm oil pressure switch, then go to step 16.
15. Check for continuity between rocker arm oil pressure switch 2P connector terminal No. 2 and body ground.
Is there continuity?
YES -
Go to step 22.
NO -
Repair open in the wire between the rocker arm oil pressure switch and G101, then go to step 16.
16. Reconnect all connectors.
17. Turn the ignition switch to ON (II).
18. Reset the PCM with the HDS.
19. Do the PCM idle learn procedure PCM Idle Learn Procedure.
20. Check for Pending or Confirmed 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 PCM, then go to step 1.
NO -
Go to step 21.
21. 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 Pending or Confirmed DTCs were indicated in step 20, go to the indicated DTC's troubleshooting.�
NO -
If the screen indicates FAILED, check for poor connections or loose terminals at the rocker arm oil pressure switch, the rocker arm oil control solenoid, and the PCM, then go to step 1. If the screen indicates NOT COMPLETED, keep idling until a result comes on.
22. Reconnect all connectors.
23. Update the PCM if it does not have the latest software PCM Update, or substitute a known-good PCM.
24. Start the engine, and let it idle.
25. Check for Pending or Confirmed DTCs with the HDS.
Is DTC P2647 indicated?
YES -
Check for poor connections or loose terminals at the rocker arm oil pressure switch, the rocker arm oil control solenoid, and the PCM. If the PCM was updated, substitute a known-good PCM, then go to step 24. If the PCM was substituted, go to step 1.
NO -
Go to step 26.
26. 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 Service and Repair. If any other Pending or Confirmed DTCs were indicated in step 25, go to the indicated DTC's troubleshooting.�
NO -
If the screen indicates FAILED, check for poor connections or loose terminals at the rocker arm oil pressure switch, the rocker arm oil control solenoid, and the PCM. If the PCM was updated, substitute a known-good PCM, then go to step 24. If the PCM was substituted, go to step 1. If the screen indicates NOT COMPLETED, keep idling until a result comes on.