What does code P21F2 mean?

Q: What does code P21F2 mean?

Cylinder 12 Injector B Circuit Low. P21F2 indicates that the powertrain control module has detected an abnormally low current flow in the electrical circuit for the fuel injector on cylinder 12, specifically the 'B' injector where the engine uses two injectors per cylinder. The computer monitors the injector driver circuit and flags this code when the return voltage or current falls below the expected threshold, which usually points to a short to ground, an open winding, or a faulty connection.

DTC codes / P21xx · Fuel and air metering / P21F2

P21F2Cylinder 12 Injector B Circuit Low

P21F2 indicates that the powertrain control module has detected an abnormally low current flow in the electrical circuit for the fuel injector on cylinder 12, specifically the 'B' injector where the engine uses two injectors per cylinder. The computer monitors the injector driver circuit and flags this code when the return voltage or current falls below the expected threshold, which usually points to a short to ground, an open winding, or a faulty connection.

SystemPowertrain

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

AreaFuel and air metering

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