DTC P2647 (KA/Kc)
DTC P2647: Rocker Arm Oil Pressure Switch Circuit High Voltage
General Description
| Logic Decision | Rocker Arm Oil Pressure Switch | |
|---|---|---|
| 'ON' | 'OFF' | |
| Rocker Arm Oil Control Solenoid Command 'ON' | Failure | Normal |
| Rocker Arm Oil Control Solenoid Command 'OFF' | Normal | Failure |
The VTEC system activates the rocker arm oil control solenoid with a command from the powertrain control module (PCM), and it charges/discharges the hydraulic circuit of the VTEC mechanism that switches valve timing between Low and High. The PCM monitors oil pressure in the hydraulic circuit of the VTEC mechanism using the rocker arm oil pressure switch downstream of the rocker arm oil control solenoid. If there is a difference between the oil pressure condition in the hydraulic circuit determined by the PCM command and the oil pressure condition determined by the status of the rocker arm oil pressure switch, the system is considered faulty, and a DTC is stored.
Monitor Execution, Sequence, Duration, DTC Type
| Execution | Once per driving cycle |
| Sequence | None |
| Duration | 2.5 seconds or more |
| DTC Type | Two drive cycles, MIL on |
Enable Conditions
| Condition | Minimum | Maximum |
|---|---|---|
| 12 volt battery voltage [BATTERY] | 10.5 V | - |
| Other | At idle | |
[ ]: HDS Parameter
Malfunction Threshold
When the rocker arm oil control solenoid is OFF, the rocker arm oil pressure switch remains OFF.
Possible Cause
NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
- Rocker arm oil control solenoid failure
- Rocker arm oil control solenoid VT SOL line open
- Rocker arm oil control solenoid VT SOL line short
- Rocker arm oil pressure switch failure
- Rocker arm oil pressure switch VTM line open
- Rocker arm oil pressure switch VTM line short
- Oil passage clogged
Confirmation Procedure
Operating Condition
Start the engine, and let it idle for at least 2.5 seconds.
With the HDS
Do the VTEC TEST in the INSPECTION MENU with the HDS.
Diagnosis Details
Conditions for setting the DTC
When a malfunction is detected during the first drive cycle, a Pending DTC is stored in the PCM memory. If the malfunction returns in the next (second) drive cycle, the MIL comes on and a Confirmed DTC and the freeze data are stored.
Conditions for clearing the DTC
The MIL is cleared if the malfunction does not return in three consecutive trips in which the diagnostic runs. The MIL, the Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command or by disconnecting the 12 volt battery.