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DTC codes / P2Dxx · Hybrid propulsion / P2D1C

P2D1CCold Start EGR A/B Ratio Performance

P2D1C indicates that during a cold start, the engine computer detected that the exhaust gas recirculation (EGR) system's A/B ratio performance is outside the expected range. The powertrain control module (PCM) monitors the EGR flow and compares the actual ratio of two sensor readings to a calibrated model, and this code sets when the measured ratio deviates beyond a threshold during the cold-start phase.

SystemPowertrain
Code typeGeneric (all makes)
SeverityMedium
Fix difficultyIntermediate
AreaHybrid propulsion

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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