EPA Approves Software Patch To Bypass Faulty DEF Sensors That Shutdown Diesel Engines
The EPA and California Air Resources Board (CARB) are working with diesel engine and vehicle manufacturers to address the growing number of reported diesel exhaust sensor failures that have left thousands of diesel engines temporarily inoperable.
The sensor monitors the quality of diesel exhaust fluid (DEF) used in the engine. When the device senses too much nitrogen oxide in the exhaust system, the engine shuts down (derates to slightly above idle) to prevent violating federal air emission standards.
The engine cannot be restarted until a new sensor is installed.
The problem is due to faulty sensors installed by manufacturers. However, the ongoing shortage of computer chips has made replacement sensors impossible to find.
To get the stalled trucks rolling again, the EPA and CARB have approved a temporary software patch that will restart engines and keep them running until the industry can obtain the computer chips needed to produce replacement sensors.
The software patch is available through vehicle and engine dealers.