What does code P223B mean?

Q: What does code P223B mean?

Reductant Heater F Control Circuit. P223B indicates that the powertrain control module has detected a fault in the control circuit for the reductant heater, which is the heating element used to keep diesel exhaust fluid (DEF) from freezing in cold weather. The computer monitors the electrical circuit that commands the heater on and off, and it sets this code when the circuit's voltage, current, or response does not match the expected values.

DTC codes / P22xx · Fuel and air metering (injector circuits) / P223B

P223BReductant Heater F Control Circuit

P223B indicates that the powertrain control module has detected a fault in the control circuit for the reductant heater, which is the heating element used to keep diesel exhaust fluid (DEF) from freezing in cold weather. The computer monitors the electrical circuit that commands the heater on and off, and it sets this code when the circuit's voltage, current, or response does not match the expected values.

SystemPowertrain

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

AreaFuel and air metering (injector circuits)

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