P26xx fault codes: Control unit and auxiliary outputs

Internal functions of the engine control unit, such as its engine-off timer, and outputs it drives, such as the fuel pump or the valve lift actuators.

How to read this code

The letter P names the system: Powertrain. The next digit, 6, locates the fault: control unit and auxiliary outputs.

These codes are generic: they mean the same thing on every make. Some manufacturer tools display them with a two-digit suffix, such as P0101-00 or P010100: the suffix refines the fault type, and the base code keeps its meaning.

The codes of this family, part by part

Engine control unit

• P2610ECM/PCM Internal Engine Off Timer Performance

Fuel pump

• P2635Fuel Pump A Low Flow/Performance

Variable valve lift (rocker arm actuator)

• P2646A Rocker Arm Actuator System Performance or Stuck Off (Bank 1)
• P2647A Rocker Arm Actuator System Stuck On (Bank 1)