P2646
DTC P2646: Rocker Arm Oil Pressure Switch (VTEC Oil Pressure Switch) Circuit Low VoltageSpecial Tools Required
- Pressure gauge adapter 07NAJ-P07010A
- A/T low pressure gauge w/panel 07406-0070300
- 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-S5A0200
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 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, system is OK at this time. Check for poor connections or loose terminals at the rocker arm oil pressure switch (VTEC oil pressure switch), the rocker arm oil control valve (VTEC solenoid valve), and the ECM.
NO - Go to step 5.
5. Turn the ignition switch OFF.
6. Disconnect the rocker arm oil pressure switch (VTEC 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 14.
NO - Go to step 9.
9. Turn the ignition switch OFF.
10. Remove the rocker arm oil pressure switch (VTEC oil pressure switch) (A) and install the special tools as shown, then attach the rocker arm oil pressure switch (VTEC oil pressure switch) (A) to the oil pressure gauge adapter (B).
NOTE: Install the switch in the reverse order of removal with a new O-ring.
11. Start the engine.
12. Do the VTEC TEST in the INSPECTION MENU with the HDS.
13. Check the oil pressure.
Does the oil pressure increase at least 392 kPa (4.0 kgf/cm.sq, 56.9 psi)?
YES - Replace the rocker arm oil pressure switch (VTEC oil pressure switch), then go to step 20.
NO - Inspect the VTEC system. If is OK, replace the rocker arm oil control valve (VTEC solenoid valve), then go to step 20.
14. Turn the ignition switch OFF.
15. Jump the SCS line with the HDS.
16. Disconnect the rocker arm oil pressure switch (VTEC oil pressure switch) 2P connector.
17. Disconnect ECM connector B (24P).
18. Check for continuity between ECM connector terminal B11 and body ground.
Is there continuity?
YES - Repair short in the wire between the ECM (B11) and the rocker arm oil pressure switch (VTEC oil pressure switch), then go to step 19.
NO - Go to step 26.
19. Reconnect all connectors.
20. Turn the ignition switch ON (II).
21. Reset the ECM with the HDS.
22. Do the ECM idle learn procedure.
23. Do the VTEC TEST in the INSPECTION MENU with the HDS.
24. Check for Temporary DTCs or DTCs with the HDS.
Are any Temporary DTCs or DTCs indicated?
YES - If DTC P2646 is indicated, check for poor connections or loose terminals at the rocker arm oil pressure switch (VTEC oil pressure switch), the rocker arm oil control valve (VTEC solenoid valve), 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 25.
25. Monitor the OBD STATUS for DTC P2646 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 23 and recheck
26. Update the ECM if it does not have the latest software, or substitute a known-good ECM.
27. Do the VTEC TEST in the INSPECTION MENU with the HDS.
28. Check for Temporary DTCs or DTCs with the HDS.
Are any Temporary DTCs or DTCs indicated?
YES - If DTC P2646 is indicated, check for poor connections or loose terminals at the rocker arm oil pressure switch (VTEC oil pressure switch), the rocker arm oil control valve (VTEC solenoid valve), 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 - If the ECM was updated, troubleshooting is complete. If the ECM was substituted, replace the original ECM.