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DTC codes / P21xx · Fuel and air metering / P21E2

P21E2Cylinder 4 Injector B Circuit Low

P21E2 indicates that the powertrain control module (PCM) has detected an abnormally low voltage or current on the control circuit for cylinder 4 injector B, which is the second injector circuit for that cylinder on engines equipped with dual injection. The PCM monitors the injector driver circuit and sets this code when the signal falls below the expected threshold, typically indicating a short to ground or an open circuit in the wiring or injector coil.

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.

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