This Preliminary Information communication provides information to the technician about vehicles that have a Service Engine Soon Malfunction Indicator Lamp on. Technician will find Diagnostic Trouble Code P0420. Technician will need to follow published Service Information diagnostics. Technician will check for a possible leak in the exhaust system behind the bank 1 sensor 2 O2 sensor. Technician will need to reposition the exhaust clamp or replace with a wider band clamp.
