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DTC codes / P21xx · Fuel and air metering / P21ED

P21EDCylinder 9 Injector B Circuit High

P21ED indicates that the powertrain control module (PCM) has detected an abnormally high voltage on the control circuit for injector B of cylinder 9, which usually means the circuit is open or shorted to power. The PCM commands the injector on and off 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.

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