Auto Systems and Repair: P0261 - OBD-II Trouble Code

OBD II Fault Code

  • OBD II P0261

Fault Code Definition
Code P0261 is triggered when the voltage in the #1 Cylinder Injector Circuit is too low. The Powertrain Control Module (PCM) uses special transistors—called "drivers"—to turn the Fuel Injectors on and off in the Fuel Injection System.


  • Check Engine Light will illuminate
  • In some cases, the engine will misfire and have a rough idle
  • In some cases, the vehicle will get poor fuel economy

Common Problems That Trigger the P0261 Code

  • Defective Fuel Injector
  • Faulty or corroded Fuel Injector, wiring, and/or connections
  • Plugged Fuel Injector
  • Dirt in the Fuel Injector

Common Misdiagnoses

  • Fuel Injector or PCM is replaced when the problem is in the wiring and connections
  • Fuel Injector is replaced when the real problem is a poor ground