P2BA9 - NOx Exceedence - Insufficient Reagent Quality

Repair Importance Level: 3/3
Repair Difficulty Level: 3/3   
Comments  |  Add Comment

Possible causes

  • Faulty NOx Sensors
  • NOx Sensors harness is open or shorted
  • NOx Sensors circuit poor electrical connection
  • Fualty Diesel Particulate Filter (DPF)

Possible symptoms

  • Engine Light ON (or Service Engine Soon Warning Light)

P2ba9 Description

The selective catalytic reduction system reduces oxides of nitrogen (NOx) emissions by injecting a metered amount of diesel exhaust fluid or reductant into the exhaust gas stream entering the diesel particulate filter (DPF). Within the selective catalytic reduction catalyst, the reductant reacts with the NOx to form nitrogen, carbon dioxide, and water vapor. Upstream and downstream NOx sensors provide the Engine Control Module (ECM) with engine-out and tailpipe-out NOx levels.

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 outlet of the turbocharger and monitors the engine out NOx. The second NOx sensor is located in the DPF that monitors NOx levels exiting the DPF. The ECM varies the amount of reductant added by varying the reductant injector duty cycle in response to changes in engine exhaust out NOx levels.

OBDII Code P2ba9 - NOx Exceedence - Insufficient Reagent Quality - AutoCodes.com

P2BA9 Information for specific makes

  • P2BA9 CHEVROLET NOx Exceedence - Insufficient Reagent Quality
  • P2BA9 DODGE NOx Exceedence - Insufficient Reagent Quality
  • P2BA9 GMC NOx Exceedence - Insufficient Reagent Quality

Need more help?

Get the P2ba9 code diagnosed by a professional: Find a repair shop in your area

Related Information

P2BA9 Comments

Help us improve AutoCodes.com. Leave a comment below or tell us if the information above help you fix the code. What are the symptoms on your vehicle for the P2ba9 code? Have you replaced any parts?
Any information is appreciated. Thanks
Top ⇧