P20EE SCR NOX Catalyst Efficiency Below Threshold Bank 1
This bulletin involves verifying the proper operation of the Diesel Exhaust Fluid (DEF)
system and, if necessary, replacing the Selective Catalyst Reduction (SCR) Catalyst
assembly.
Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further
investigation the technician may find Diagnostic Trouble Code (DTC) P20EE SCR NOX
Catalyst Efficiency Below Threshold Bank 1 set in the Powertrain Control Module (PCM)
memory.