P2BAE Possible Causes
- Faulty NOx sensors
- NOx sensor wiring harness is open or short-circuited
- Poor electrical connection in the NOx sensor circuit
- Diesel Particulate Filter (DPF)
How to Fix P2BAE Code
Check the “Possible Causes” listed above. Visually inspect the wiring harness and related connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.
Possible Symptoms
Check Engine Light illuminated (or Service Engine Soon warning light)
P2BAE Meaning
The Selective Catalytic Reduction system reduces nitrogen oxide (NOx) emissions by injecting a measured amount of diesel exhaust fluid or reductant into the exhaust gas stream entering the Diesel Particulate Filter (DPF). In the Selective Catalytic Reduction catalyst, the reductant reacts with NOx to form nitrogen, carbon dioxide, and water vapor. The upstream and downstream NOx sensors provide the Engine Control Module (ECM) with NOx levels from the engine output and exhaust output.
The ECM uses the 2 NOx sensors to control exhaust NOx levels. The NOx sensor measures the amount of NOx and oxygen in the exhaust system. The first NOx sensor is located at the turbocharger outlet and monitors the engine’s NOx emissions. The second NOx sensor is located in the DPF and monitors the NOx levels exiting the DPF. The ECM varies the amount of reductant added by adjusting the reductant injector duty cycle in response to changes in the engine’s exhaust NOx levels.