What does code P21D2 mean?

Q: What does code P21D2 mean?

Cylinder 4 Injector B Circuit/Open. P21D2 indicates that the powertrain control module has detected an open circuit or excessive resistance in the control circuit for cylinder 4 injector B, which is the second injector assigned to that cylinder on engines using dual injection. The computer monitors the commanded injector current and flags the code when the circuit does not respond as expected, meaning the injector may not be firing at all.

DTC codes / P21xx · Fuel and air metering / P21D2

P21D2Cylinder 4 Injector B Circuit/Open

P21D2 indicates that the powertrain control module has detected an open circuit or excessive resistance in the control circuit for cylinder 4 injector B, which is the second injector assigned to that cylinder on engines using dual injection. The computer monitors the commanded injector current and flags the code when the circuit does not respond as expected, meaning the injector may not be firing at all.

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.