P0421 Audi
Warm Up Catalyst Efficiency Below Threshold Bank 1
Audi
P0422 Audi
Main Catalyst Efficiency Below Threshold Bank 1
P0423 Audi
Heated Catalyst Efficiency Below Threshold Bank 1
P0424 Audi
Heated Catalyst Temperature Below Threshold Bank 1
P0425 Audi
Catalyst Temperature Sensor Circuit Bank 1 Sensor 1
P0426 Audi
Catalyst Temperature Sensor Range/Performance Bank 1 Sensor 1
P0412 Audi
Secondary Air Injection System Switching Valve ‘A’ Circuit Malfunction
P0413 Audi
Secondary Air Injection System Switching Valve ‘A’ Circuit Open
P0414 Audi
Secondary Air Injection System Switching Valve ‘A’ Circuit Shorted
P0416 Audi
Secondary Air Injection System Switching Valve ‘B’ Circuit Open