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DTC P2EC7

DTC P2EC7:  Cold Start Rocker Arm Oil Control System Problem

General Description 

GHH416948Courtesy of HONDA, U.S.A., INC.
Logic Decision Rocker Arm Oil Pressure Switch
'ON' 'OFF'
Rocker Arm Oil Control Solenoid Command 'OFF' Normal Failure

The cold start emission reduction strategy controls air fuel ratio to lean when the engine is started at cold condition to lower the emission while the catalyst is not warmed up enough. If there is a difference between the oil pressure condition in the hydraulic circuit determined by the powertrain control module (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 15.5 seconds or more
DTC Type Two drive cycles, MIL on

Enable Conditions 

Condition Minimum Maximum
12 volt battery voltage [Battery] 10.5 V -
Engine coolant temperature [ECT Sensor 1] 14 deg.F (-10 deg.C) 176 deg.F (80 deg.C)
High voltage battery capacity (SOC) 20 %  
Quick warm-up system Operation
Accelerator pedal position Released
Other Vehicle stopped

[ ]: 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 VTS line open
  • Rocker arm oil control solenoid VTS 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 

  1. Leave the vehicle to cool the engine.
  2. Enter the maintenance mode, then start the engine, and let it idle for at least 15.5 seconds.

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.