What does code P24E7 mean?

Q: What does code P24E7 mean?

NH3 Sensor Heater Circuit Low. P24E7 indicates that the powertrain control module has detected an abnormally low current or voltage on the heater circuit for the ammonia (NH3) sensor, which is used in selective catalytic reduction systems to monitor NOx conversion efficiency. The heater is responsible for bringing the sensor up to operating temperature quickly, and a low circuit condition means the heater is not drawing the expected current, often due to an open circuit or high resistance.

DTC codes / P24xx · Auxiliary emission controls / P24E7

P24E7NH3 Sensor Heater Circuit Low

P24E7 indicates that the powertrain control module has detected an abnormally low current or voltage on the heater circuit for the ammonia (NH3) sensor, which is used in selective catalytic reduction systems to monitor NOx conversion efficiency. The heater is responsible for bringing the sensor up to operating temperature quickly, and a low circuit condition means the heater is not drawing the expected current, often due to an open circuit or high resistance.

SystemPowertrain

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

AreaAuxiliary emission controls

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