P2648

DTC P2648: Rocker Arm Oil Control Solenoid Circuit Low Voltage

NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information.

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 and the ECM.

NO - Go to step 4.

4. Turn the ignition switch OFF.
5. Disconnect the rocker arm oil control solenoid 2P connector.




6. Measure resistance between rocker arm oil control solenoid 2P connector terminals No. 1 and No. 2.

Is there 14-30 Ohm at room temperature?

YES - Go to step 7.

NO - Go to step 10.

7. Jump the SCS line with the HDS.
8. Disconnect ECM connector B (44P).




9. Check for continuity between ECM connector terminal B34 and body ground.

Is there continuity?

YES - Repair short in the wire between the ECM (B34) and the rocker arm oil control solenoid, then go to step 11.

NO - Go to step 18.

10. Replace the rocker arm oil control valve.
11. Reconnect all connectors.
12. Turn the ignition switch ON (II).
13. Reset the ECM with the HDS.
14. Do the ECM idle learn procedure.
15. Do the VTEC TEST in the INSPECTION MENU with the HDS.
16. Check for Temporary DTCs or DTCs with the HDS.

Are any Temporary DTCs or DTCs indicated?

YES - If DTC P2648 is indicated, check for poor connections or loose terminals at the rocker arm oil control solenoid and the ECM, then go to step 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.

NO - Go to step 17.

17. Monitor the OBD STATUS for DTC P2648 in the DTCs MENU with the HDS.

Does the screen indicate PASSED?

YES - Troubleshooting is complete.

NO - If the screen indicates FAILED, go to step 1 and recheck. If the screen indicates NOT COMPLETED, go to step 15 and recheck.

18. Update the ECM if it does not have the latest software, or substitute a known-good ECM.
19. Do the VTEC TEST in the INSPECTION MENU with the HDS.
20. Check for Temporary DTCs or DTCs with the HDS.

Is DTC P2648 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, then go to step 19. If the ECM was substituted, go to step 1.

NO - If no Temporary DTCs or DTCs are indicated, go to step 21. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.

21. Monitor the OBD STATUS for DTC P2648 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

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, then go to step 19. If the ECM was substituted, go to step 1. If the screen indicates EXECUTING, keep driving until a result comes on. If the screen indicates OUT OF CONDITION, go to step 19 and recheck.