What does code P2A37 mean?

Q: What does code P2A37 mean?

AFCM Power Relay Sense Circuit High. P2A37 indicates that the AFCM (Alternator/Generator Control Module) has detected a high voltage on its power relay sense circuit, meaning the module sees the relay control line stuck at or near battery voltage when it should be low or pulsing. The AFCM monitors this circuit to confirm the power relay is functioning correctly, and a high reading tells the module that the relay coil or its wiring is not being commanded properly.

DTC codes / P2Axx · Hybrid propulsion / P2A37

P2A37AFCM Power Relay Sense Circuit High

P2A37 indicates that the AFCM (Alternator/Generator Control Module) has detected a high voltage on its power relay sense circuit, meaning the module sees the relay control line stuck at or near battery voltage when it should be low or pulsing. The AFCM monitors this circuit to confirm the power relay is functioning correctly, and a high reading tells the module that the relay coil or its wiring is not being commanded properly.

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.