What does code P031D mean?

Q: What does code P031D mean?

Ignition D Control Signal Circuit/Open. P031D indicates that the powertrain control module (PCM) has detected an open circuit or abnormal condition on the ignition control signal circuit for cylinder D, which is typically the fourth cylinder in the engine's firing order. The PCM commands a spark event but does not see the expected electrical response from the ignition coil or ignition control module, so it sets this code and may illuminate the check engine light.

DTC codes / P03xx · Ignition system and misfire / P031D

P031DIgnition D Control Signal Circuit/Open

P031D indicates that the powertrain control module (PCM) has detected an open circuit or abnormal condition on the ignition control signal circuit for cylinder D, which is typically the fourth cylinder in the engine's firing order. The PCM commands a spark event but does not see the expected electrical response from the ignition coil or ignition control module, so it sets this code and may illuminate the check engine light.

SystemPowertrain

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

AreaIgnition system and misfire

Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.