P0256 OBD II Trouble Code Injection Pump Fuel Metering Control B Malfunction (Cam/Rotor/Injector)

How to easily diagnose, repair, and what causes a P0256 code which indicates a malfunction in the B injection pump fuel metering control.

Symptoms of P0256 OBD II Trouble Code

  • Malfunction Indicator Lamp (MIL) illumination
  • Decrease in fuel economy

Common Causes of P0256 OBD II Trouble Code

  • Open in the signal circuit to the FRP sensor - possible
  • Short to voltage in the signal circuit to the FRP sensor - possible
  • Short to ground in the signal circuit to the FRP sensor - possible
  • Open in power or ground at FRP sensor - possible
  • Failed FRP Sensor - likely
  • Failed PCM - unlikely

Severity of P0256 OBD II Trouble Code

Severity in this case will be not severe. Since it is electrical failure, the PCM can compensate adequately for it.