PZEV models
DTC Troubleshooting: P2646, P2647
DTC P2646:
Rocker Arm Oil Pressure Switch A Circuit Low Voltage (PZEV model)
DTC P2647:
Rocker Arm Oil Pressure Switch A Circuit High Voltage (PZEV model)
Special Tools Required
- Pressure Gauge Adapter 07NAJ-P07010A
- A/T Low Pressure Gauge w/Panel 07406-0070301
- A/T Pressure Test Hose 07AAJ-PY4A100
- 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 Initial Inspection and Diagnostic Overview.
- If DTC P2648 and/or P2649 are stored at the same time as DTC P2646 and/or P2647, troubleshoot those DTCs first, then recheck for DTC P2646 and/or P2647.
1. Check the engine oil level.
Is the level OK?
YES -
Go to step 2.
NO -
Adjust the engine oil level to the proper level, then go to step 29.
2. Turn the ignition switch to ON (II).
3. Clear the DTC with the HDS.
4. Select the VTEC TEST in the INSPECTION MENU with the HDS, and do the VTEC TEST.
Are VTECIN-0 and VTECEX-0 indicated?
YES -
Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at rocker arm oil pressure switch A, rocker arm oil control solenoid A, and the PCM.�
NO -
If the result is
- VTECIN-1: Go to step 5.
- VTECIN-3: Go to step 14.
- VTECIN-3 and VTECEX-3 indicated at the same time: Check the oil passage between the engine oil pressure switch and the rocker arm oil control valve filter. If it is OK, go to step 14.
- VTECIN-2, VTECIN-4: Inspect the intake valve side of the VTEC system. If it is OK, replace the rocker arm oil control valve Rocker Arm Oil Control Valve Removal/Installation (PZEV Models), then go to step 29.
- VTECEX-1, 2, 3, 4: The exhaust valve side VTEC system is faulty. Go to the troubleshooting for DTC P2651/P2652 P2651.
5. Turn the ignition switch to LOCK (0).
6. Disconnect the rocker arm oil pressure switch A 2P connector.
7. At rocker arm oil pressure switch A side, check for continuity between its 2P connector terminals.
Is there continuity?
YES -
Go to step 8.
NO -
Replace rocker arm oil pressure switch A Rocker Arm Oil Pressure Switch A Removal/Installation (PZEV Models), then go to step 29.
8. Turn the ignition switch to ON (II).
9. Measure the voltage between rocker arm oil pressure switch A 2P connector terminal No. 1 and body ground.
Is there battery voltage?
YES -
Repair open in the wire between rocker arm oil pressure switch A and G101, then go to step 28.
NO -
Go to step 10.
10. Turn the ignition switch to LOCK (0).
11. Jump the SCS line with the HDS.
12. Disconnect PCM connector C (49P).
13. Check for continuity between rocker arm oil pressure switch A 2P connector terminal No. 1 and PCM connector terminal C22.
Is there continuity?
YES -
Check for poor connections or loose terminals at rocker arm oil pressure switch A, rocker arm oil control solenoid A, and the PCM. If the connections and terminals are OK, go to step 35.
NO -
Repair open in the wire between rocker arm oil pressure switch A and the PCM (C22), then go to step 29.
14. Turn the ignition switch to LOCK (0).
15. Disconnect the rocker arm oil pressure switch A 2P connector.
16. Turn the ignition switch to ON (II).
17. Check ROCKER ARM OIL PRESSURE SWITCH A in the DATA LIST with the HDS.
Is SWITCH ON indicated?
YES -
Go to step 24.
NO -
Go to step 18.
18. Turn the ignition switch to LOCK (0).
19. Remove rocker arm oil pressure switch A Rocker Arm Oil Pressure Switch A Removal/Installation (PZEV Models), then reinstall the rocker arm oil control valve and its filter Rocker Arm Oil Control Valve Removal/Installation (PZEV Models) without installing rocker arm oil pressure switch A.
20. Attach the special tools to the rocker arm oil control valve as shown, then attach rocker arm oil pressure switch A to the oil pressure gauge adapter (B).
21. Reconnect the rocker arm oil pressure switch A 2P connector.
22. Select the VTEC TEST in the INSPECTION MENU with the HDS, and do the VTEC TEST.
23. Check the oil pressure during the High V/T/LIFT (TEST STATUS 4).
Does the oil pressure increase to at least 191 kPa (2.0 kgf/cm 2, 27.7 psi)?
YES -
Replace rocker arm oil pressure switch A Rocker Arm Oil Pressure Switch A Removal/Installation (PZEV Models), then go to step 29.
NO -
Inspect the intake valve side of the VTEC system. If it is OK, replace the rocker arm oil control valve Rocker Arm Oil Control Valve Removal/Installation (PZEV Models), then go to step 29.
24. Turn the ignition switch to LOCK (0).
25. Jump the SCS line with the HDS.
26. Disconnect PCM connector C (49P).
27. 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 rocker arm oil pressure switch A, then go to step 29.
NO -
Check for poor connections or loose terminals at rocker arm oil pressure switch A, rocker arm oil control solenoid A, and the PCM. If the connectors and the terminals are OK, go to step 35.
28. Turn the ignition switch to LOCK (0).
29. Reconnect all connectors.
30. Turn the ignition switch to ON (II).
31. Reset the PCM with the HDS.
32. Do the PCM idle learn procedure ECM/PCM Idle Learn Procedure (A/T).
33. Select the VTEC TEST in the INSPECTION MENU with the HDS, and do the VTEC TEST.
Are VTECIN-0 and VTECEX-0 indicated?
YES -
Go to step 34.
NO -
Check for poor connections or loose terminals at rocker arm oil pressure switch A, rocker arm oil control solenoid A, and the PCM, then go to step 1.
34. Check for Pending or Confirmed DTCs with the HDS.
Are any Pending or Confirmed DTCs indicated?
YES -
If any other Pending or Confirmed DTCs are indicated, go to the indicated DTC's troubleshooting.�
NO -
Troubleshooting is complete.�
35. Reconnect all connectors.
36. Update the PCM if it does not have the latest software ECM/PCM Update, or substitute a known-good PCM.
37. Select the VTEC TEST in the INSPECTION MENU with the HDS, and do the VTEC TEST.
Are VTECIN-0 and VTECEX-0 indicated?
YES -
Go to step 38.
NO -
If the PCM was updated, substitute a known-good PCM, then recheck. If the PCM was substituted, go to step 1.
38. Check for Pending or Confirmed DTCs with the HDS.
Are any Pending or Confirmed DTCs indicated?
YES -
If any other Pending or Confirmed DTCs are indicated, go to the indicated DTC's troubleshooting.�
NO -
If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the original PCM Service and Repair.�