What does code P21DF mean?

Q: What does code P21DF mean?

Cylinder 2 Injector B Circuit High. P21DF indicates that the powertrain control module (PCM) has detected an abnormally high voltage on the control circuit for fuel injector B in cylinder 2, which usually means the circuit is open or shorted to voltage. The PCM commands the injector on by grounding the circuit, so a high-voltage reading tells the module that current is not flowing as expected.

DTC codes / P21xx · Fuel and air metering / P21DF

P21DFCylinder 2 Injector B Circuit High

P21DF indicates that the powertrain control module (PCM) has detected an abnormally high voltage on the control circuit for fuel injector B in cylinder 2, which usually means the circuit is open or shorted to voltage. The PCM commands the injector on by grounding the circuit, so a high-voltage reading tells the module that current is not flowing as expected.

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.