– Faulty Rocker Arm Oil Control Solenoid
– Faulty EOP (Engine Oil Pressure) sensor
– Incorrect oil type used
– Engine mechanical condition
The VTEC system activates rocker arm oil control solenoid B by 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 rocker arm oil pressure switch B downstream of rocker arm oil control solenoid B. 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 rocker arm oil pressure switch B, the system is considered faulty, and a DTC is stored.