DTC Troubleshooting
DTC P2646: Rocker Arm Oil Pressure Switch Circuit Low VoltageSpecial Tools Required
- Pressure gauge adapter 07NAJ-P07010A
- A/T low pressure gauge w/panel 07406-0070301
- A/T pressure hose 07406-0020201
- A/T pressure hose, 2,210 mm 07MAJ-PY4011A
- A/T pressure adapter 07MAJ-PY40120
- Oil pressure hose 07ZAJ-S5AA200
NOTE: 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 20.
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, the rocker arm oil control solenoid, and the PCM.
NO - Go to step 5.
5. Turn the ignition switch OFF.
6. Disconnect the rocker arm oil pressure switch 2P connector.
7. Turn the ignition switch ON (II).
8. Check the VTEC PRES SW in the DATA LIST with the HDS.
Is SWITCH ON indicated?
YES - Go to step 16.
NO - Go to step 9.
9. Turn the ignition switch OFF.
10. Remove the charge air cooler cover.
11. Remove the rocker arm oil pressure switch (A), and install the special tools as shown, then install the rocker arm oil pressure switch on the oil pressure gauge attachment (B).
NOTE: Install the switch in the reverse order of removal with a new O-ring.
12. Reconnect the rocker arm oil pressure switch 2P connector.
13. Start the engine.
14. Do the VTEC TEST in the INSPECTION MENU with the HDS.
15. Check the oil pressure.
Does the oil pressure increase to at least 392 kPa (4.0 kgf/sq.cm, 56.9 psi)?
YES - Replace the rocker arm oil pressure switch, then go to step 20.
NO - Inspect the VTEC system. If it is OK, replace the rocker arm oil control solenoid, then go to step 20.
16. Turn the ignition switch OFF.
17. Jump the SCS line with the HDS.
18. Disconnect PCM connector C (44P).
19. Check for continuity between PCM connector terminal C22 and body ground.
Is there continuity?
YES - Repair short in the wire between the PCM (C22) and the rocker arm oil pressure switch, then go to step 20.
NO - Go to step 27.
20. Reconnect all connectors.
21. Turn the ignition switch ON (II).
22. Reset the PCM with the HDS.
23. Do the PCM idle learn procedure.
24. Do the VTEC TEST in the INSPECTION MENU with the HDS.
25. Check for Temporary DTCs or DTCs with the HDS.
Is DTC P2646 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, then go step 1.
NO - Go to step 26.
26. Monitor the OBD STATUS for DTC P2646 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 25, 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, the rocker arm oil control solenoid, and the PCM, then go to step 1. If the screen indicates NOT COMPLETED, go to step 24.
27. Reconnect all connectors.
28. Update the PCM if it does not have the latest software, or substitute a known-good PCM.
29. Do the VTEC TEST in the INSPECTION MENU with the HDS.
30. Check for Temporary DTCs or DTCs with the HDS.
Is DTC P2646 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 29. If the PCM was substituted, go to step 1.
NO - Go to step 31.
31. Monitor the OBD STATUS for DTC P2646 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. If any other Temporary DTCs or DTCs were indicated in step 30, 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, the rocker arm oil control solenoid, and the PCM. If the PCM was updated, substitute a known-good PCM, then go to step 29. If the PCM was substituted, go to step 1. If the screen indicates NOT COMPLETED, go to step 29.