With M/T

DTC Troubleshooting: P2649

DTC P2649: Rocker Arm Oil Control Solenoid 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. Turn the ignition switch to ON (II).

2. Clear the DTC with the HDS.

3. Start the engine. Hold the engine speed at 3,000 rpm without load (in neutral) until the radiator fan comes on, then let it idle.

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

Is DTC P2649 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 rocker arm oil control solenoid and the ECM.


5. Turn the ignition switch to LOCK (0).

6. Disconnect the rocker arm oil control solenoid 1P connector.

7. At the solenoid side, measure the resistance between the rocker arm oil control solenoid 1P connector terminal and the solenoid valve body.

Is there 14-30 Ohms at room temperature?
YES - Go to step 8.

NO - Go to step 11.






8. Jump the SCS line with the HDS.

9. Disconnect ECM connector B (49P).

10. Check for continuity between ECM connector terminal B39 and the rocker arm oil control solenoid 1P connector terminal.

Is there continuity?
YES - Go to step 18.

NO - Repair open in the wire between the ECM (B39) and the rocker arm oil control solenoid, then go to step 12.






11. Replace the rocker arm oil control solenoid. Rocker Arm Oil Control Solenoid Replacement (M/T)

12. Reconnect all connectors.

13. Turn the ignition switch to ON (II).

14. Reset the ECM with the HDS.

15. Do the ECM idle learn procedure. ECM/PCM Idle Learn Procedure

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

Is DTC P2649 indicated?
YES - Check for poor connections or loose terminals at the rocker arm oil control solenoid and the ECM, then go to step 1.

NO - Go to step 17.


17. Monitor the OBD STATUS for DTC P2649 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 16, go to the indicated DTC's troubleshooting.

NO - If the screen indicates FAILED, go to step 1 and recheck. If the screen indicates NOT COMPLETED, keep idling until a result comes on.


18. Reconnect all connectors.

19. Update the ECM if it does not have the latest software, ECM/PCM Update or substitute a known-good ECM. Initial Inspection and Diagnostic Overview

20. Start the engine, and let it idle.

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

Is DTC P2649 indicated?
YES - Check for poor connections or loose terminals at the rocker arm oil control solenoid and the ECM. If the ECM was updated, substitute a known-good ECM, Initial Inspection and Diagnostic Overview then recheck. If the ECM was substituted, go to step 1.

NO - Go to step 22.


22. Monitor the OBD STATUS for DTC P2649 in the DTCs MENU with the HDS.

Does the screen indicate PASSED?
YES - If the ECM was updated, troubleshooting is complete. If the ECM was substituted, replace the original ECM. Service and Repair If any other Temporary DTCs or DTCs were indicated in step 21, 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 control solenoid and the ECM. If the ECM was updated, substitute a known-good ECM, Initial Inspection and Diagnostic Overview then recheck. If the ECM was substituted, go to step 1. If the screen indicates NOT COMPLETED, keep idling until a result comes on.