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DTC codes / P20xx · Fuel and air metering and auxiliary emission controls / P2051

P2051Reductant Injector Circuit Low (Bank 2 Unit 1)

P2051 means the engine control module has detected an abnormally low current flow in the reductant injector circuit for bank 2 unit 1, which is part of the diesel exhaust fluid injection system. The computer expects a specific current draw when it commands the injector, and a reading below the threshold indicates an open circuit, high resistance, or a failed injector coil.

SystemPowertrain
Code typeGeneric (all makes)
SeverityMedium
Fix difficultyIntermediate
AreaFuel and air metering and auxiliary emission controls

Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.

Running on fumes Free guides aren't free to make. Top up the tank. Any amount, one time. Fuel the Garage