This code indicates an intermittent electrical fault within the heater circuit of the Nitrogen Oxide (NOx) sensor located on engine Bank 2. It suggests the sensor is not maintaining consistent communication regarding its heating element status, which is required for accurate emissions monitoring. This condition typically occurs in diesel engines equipped with selective catalytic reduction (SCR) systems.
Heat and vibration near the exhaust often crack insulation or corrode terminals in the sensor harness.
The internal heating component within the sensor itself frequently fails due to thermal stress.
A compromised power supply to the sensor heater circuit can cause intermittent operation.
Leaks can alter temperatures and affect sensor performance or damage wiring harnesses.
Outdated control module software may misinterpret valid sensor signals as faults.
Internal circuitry failure is rare but possible if all external components and wiring test correctly.
While the vehicle may run, prolonged driving can damage the SCR system and lead to reduced power modes.
No, this code is almost always caused by the sensor or wiring, not the PCM.
No, resetting clears the light temporarily, but the underlying electrical fault will trigger the code again.
Bank 2 refers to the side of the engine that does not contain cylinder number 1, or the downstream sensor location depending on the manufacturer.