DTC Troubleshooting
DTC P2648: Rocker Arm Oil Control Solenoid Circuit Low VoltageNOTE: 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, system is OK at this time. Check for poor connections or loose terminals at the rocker arm oil control solenoid and the ECM/PCM.
NO - Go to step 4.
4. Turn the ignition switch OFF.
5. Disconnect the rocker arm oil control solenoid 2P connector.
6. At the solenoid side, measure resistance between rocker arm oil control solenoid 2P connector terminals No. 1 and No. 2.
Is there 14 - 17 ohms at room temperature?
YES - Go to step 7.
NO - Go to step 10.
7. Jump the SCS line with the HDS.
8. Disconnect ECM/PCM connector B (24P).
9. Check for continuity between ECM/PCM connector terminal B6 and body ground.
Is there continuity?
YES - Repair short in the wire between the ECM/PCM (B6) 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/PCM with the HDS.
14. Do the ECM/PCM 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.
Is DTC P2648 indicated?
YES - Check for poor connections or loose terminals at the rocker arm oil control solenoid and the ECM/PCM, then go to step 1.
NO - If Temporary DTC or DTC P2648 is not indicated, or if any other Temporary DTCs or DTCs are indicated, 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 - If there was no Temporary DTCs or DTCs indicated on step 16, troubleshooting is complete. If any other Temporary DTCs or DTCs was indicated on 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, go to step 15 and recheck.
18. Update the ECM/PCM if it does not have the latest software, or substitute a known-good ECM/PCM.
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/PCM. If the ECM/PCM was updated, substitute a known-good ECM/PCM, then go to step 19. If the ECM/PCM was substituted, go to step 1.
NO - If Temporary DTC or DTC P2648 is not indicated, or if any other Temporary DTCs or DTCs are indicated, go to step 21.
21. Monitor the OBD STATUS for DTC P2648 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 was indicated on 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 control solenoid and the ECM/PCM. If the ECM/PCM was updated, substitute a known-good ECM/PCM, then go to step 19. If the ECM/PCM was substituted, go to step 1. If the screen indicates NOT COMPLETED, go to step 19 and recheck.