July 1: So it begins. Don't worry, this is not in the correct legal jurisdiction!

DTC P0420 Or P0430: Catalyst System Efficiency Below Threshold: Notes

NOTE: Bank No. 1 refers to bank that includes cylinder No. 1. Bank No. 2 refers to bank without cylinder No. 1. Oxygen sensor No. 1 refers to sensor closest to engine block. Oxygen sensor No. 2 refers to sensor furthest away from engine block.