P256B - OBD II Trouble Code

January 31, 2017

Our automotive experts have put together the following information about the P256B diagnostic trouble code. We've provided the common symptoms that occur when this code is set along with the frequent repairs that address the issues related to the P256B code.

OBD II Fault Code

  • OBD II P256B

OBD-II Code Engine may stall is defined as a Engine Idle Speed Selector Sensor/Switch Range/Performance

The Idle Control Valve (Idle Speed Selector overseas) controls the engine's idle speed. If the idle speed can not be properly maintained as requested by the engine computer, code P256B will be stored.

Engine may stall Symptoms

  • Engine may stall

Common Problems That Trigger the P256B Code

  • Idle Air Control (IAC) valve failure
  • Powertrain Control Module (PCM) failure
  • Wiring issue

About the Author

Brad Kava is an automotive expert at RepairPal, the leading online source of auto repair resources and estimates. With many ASE Master certified mechanics on staff who have decades of experience, RepairPal knows all the fine points of car repair.

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