DTC P2648 (KA/Kc)
DTC P2648: Rocker Arm Oil Control Solenoid Circuit Low Voltage
General Description
The VTEC system activates the rocker arm oil control solenoid by 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. If the return signal is OFF (low) when the PCM outputs the ON (high) signal to the rocker arm oil control solenoid, the PCM detects a malfunction and stores a DTC.
Monitor Execution, Sequence, Duration, DTC Type
| Execution | Continuous |
| Sequence | None |
| Duration | 2.0 seconds or more |
| DTC Type | One drive cycle, MIL on |
Enable Conditions
| Condition | Minimum | Maximum |
|---|---|---|
| 12 volt battery voltage [BATTERY] | 10.0 V | - |
[ ]: HDS Parameter
Malfunction Threshold
The return signal is OFF (low) for at least 2.0 seconds when the PCM outputs the ON (high) signal to the rocker arm oil control solenoid.
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 VT SOL line short to ground
- Rocker arm oil control solenoid failure
- PCM internal circuit failure
Confirmation Procedure
Operating Condition
- Start the engine. Hold the engine speed [ENGINE SPEED] at 3, 000 rpm without load (CVT in P or N, M/T in neutral) until the radiator fan comes on.
- Drive the vehicle at a steady speed of 2 mph (3 km/h)* 1 (1 mph (2 km/h))* 2 or more at a steady engine speed [ENGINE SPEED]2, 000 - 2, 800 rpm* 1 (1, 300 - 2, 800 rpm)* 2 or more for at least 2 seconds.
- Drive the vehicle in this manner only if the traffic regulations and ambient conditions allow.
*1: MT model
*2: CVT model
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, the MIL comes on and a Pending DTC, a Confirmed DTC, and the freeze data are stored in the PCM memory.
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.