DTC Troubleshooting
Control System DTCs
DTC Troubleshooting: P2647
DTC P2647 : Rocker Arm Oil Pressure Switch Circuit High Voltage
NOTE:
* Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information How To Troubleshoot The Fuel And Emissions Systems.
* If DTC P2648 and/or P2649 are stored at the same time as DTC P2647, troubleshoot those DTCs first, then recheck for DTC P2647.
1. Oil level check:
Oil level check
-1. Check the engine oil level.
Is the level OK?
-YES- Go to step 2.
-NO- Adjust the engine oil to the proper level Testing and Inspection, then do the repair verification.
2. Problem verification:
Problem verification
-1. Do the VTEC TEST in the INSPECTION MENU with the HDS.
NOTE: If DTC P2647 is indicated, go to step 6. If any other Pending or Confirmed DTCs are indicated, go to the indicated DTC's troubleshooting.
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 ECM.
-NO- Go to step 3.
3. Determination of possible failure area (Rocker arm oil control solenoid, others):
Determination of possible failure area (Rocker arm oil control solenoid, others)
-1. Check the result of VTEC TEST.
Is VTEC Switch Failure, VTEC Switch Open, VTEC Switch SIG Line Open, or VTEC Switch GND Line Open indicated?
-YES- Go to step 4.
-NO- Check for poor connections or loose terminals at the rocker arm oil pressure switch. If it is OK, replace the rocker arm oil control valve Rocker Arm Oil Control Valve Removal and Installation, then do the repair verification.
4. Rocker arm oil pressure switch internal resistance check:
Rocker arm oil pressure switch internal resistance check
-1. Turn the ignition switch to LOCK (0).
-2. Disconnect the following connector.
-3. At the rocker arm oil pressure switch side, check for continuity between test points 1 and 2.
Is there continuity?
-YES- Go to step 5.
-NO- Replace the rocker arm oil pressure switch Service and Repair, then do the repair verification..
5. Open wire check (LG2 line):
Open wire check (LG2 line)
-1. Turn the ignition switch to ON (II.).
-2. Measure the voltage between test points 1 and 2.
Is there about 5.0 V?
-YES- The VT_SW_IN wire is OK. Repair an open in the LG2 wire between the rocker arm oil pressure switch and G101, then do the repair verification.
-NO- Go to step 6.
6. Open wire check (VT_SW_IN line):
Open wire check (VT_SW_IN line)
-1. Turn the ignition switch to LOCK (0).
-2. Jump the SCS line with the HDS.
-3. Disconnect the following connector.
-4. Check for continuity between test points 1 and 2.
Is there continuity?
-YES- The VT_SW_IN wire is OK. Update the ECM ECM/PCM Update if it does not have the latest software, or substitute a known-good ECM Service and Repair, then do the repair verification.
-NO- Repair an open in the VT_SW_IN wire between the rocker arm oil pressure switch and the ECM (C13), then do the repair verification.
Repair verification:
-1. Reconnect all connectors.
-2. Turn the ignition switch to ON (II.).
-3. Reset the ECM with the HDS How To Troubleshoot The Fuel And Emissions Systems.
-4. Do the ECM idle learn procedure ECM/PCM Idle Learn Procedure.
-5. Start the engine, and let it idle.
-6. Check for Pending or Confirmed DTCs with the HDS.
Is DTC P2647 indicated?
-YES- Check for poor connections or loose terminals at the rocker arm oil pressure switch, the rocker arm oil control solenoid, and the ECM. If the ECM was updated, substitute a known-good ECM Service and Repair, then recheck. If the ECM was substituted, go to step 1.
-NO- Troubleshooting is complete. If the ECM was substituted, replace the original ECM Service and Repair. If any other Pending or Confirmed DTCs are indicated, go to the indicated DTC's troubleshooting.