From Faq
P0400 - P499 Auxilliary Emission Controls
P0400 Exhaust Gas Recirculation Flow
P0401 Exhaust Gas Recirculation Flow Insufficient Detected
P0402 Exhaust Gas Recirculation Flow Excessive Detected
P0403 Exhaust Gas Recirculation Control Circuit
P0404 Exhaust Gas Recirculation Control Circuit Range/Performance
P0405 Exhaust Gas Recirculation Sensor "A" Circuit Low
P0406 Exhaust Gas Recirculation Sensor "A" Circuit High
P0407 Exhaust Gas Recirculation Sensor "B" Circuit Low
P0408 Exhaust Gas Recirculation Sensor "B" Circuit High
P0409 Exhaust Gas Recirculation Sensor "A" Circuit
P0410 Secondary Air Injection System
P0411 Secondary Air Injection System Incorrect Flow Detected
P0412 Secondary Air Injection System Switching Valve "A" Circuit
P0413 Secondary Air Injection System Switching Valve "A" Circuit Open
P0414 Secondary Air Injection System Switching Valve "A" Circuit Shorted
P0415 Secondary Air Injection System Switching Valve "B" Circuit
P0416 Secondary Air Injection System Switching Valve "B" Circuit Open
P0417 Secondary Air Injection System Switching Valve "B" Circuit Shorted
P0418 Secondary Air Injection System Control "A" Circuit
P0419 Secondary Air Injection System Control "B" Circuit
P0420 Catalyst System Efficiency Below Threshold Bank 1
P0421 Warm Up Catalyst Efficiency Below Threshold Bank 1
P0422 Main Catalyst Efficiency Below Threshold Bank 1
P0423 Heated Catalyst Efficiency Below Threshold Bank 1
P0424 Heated Catalyst Temperature Below Threshold Bank 1
P0425 Catalyst Temperature Sensor Bank 1
P0426 Catalyst Temperature Sensor Range/Performance Bank 1
P0427 Catalyst Temperature Sensor Low Bank 1
P0428 Catalyst Temperature Sensor High Bank 1
P0429 Catalyst Heater Control Circuit Bank 1
P0430 Catalyst System Efficiency Below Threshold Bank 2
P0431 Warm Up Catalyst Efficiency Below Threshold Bank 2
P0432 Main Catalyst Efficiency Below Threshold Bank 2
P0433 Heated Catalyst Efficiency Below Threshold Bank 2
P0434 Heated Catalyst Temperature Below Threshold Bank 2
P0435 Catalyst Temperature Sensor Bank 2
P0436 Catalyst Temperature Sensor Range/Performance Bank 2
P0437 Catalyst Temperature Sensor Low Bank 2
P0438 Catalyst Temperature Sensor High Bank 2
P0439 Catalyst Heater Control Circuit Bank 2
P0440 Evaporative Emission System
P0441 Evaporative Emission System Incorrect Purge Flow
P0442 Evaporative Emission System Leak Detected (small leak)
P0443 Evaporative Emission System Purge Control Valve Circuit
P0444 Evaporative Emission System Purge Control Valve Circuit Open
P0445 Evaporative Emission System Purge Control Valve Circuit Shorted
P0446 Evaporative Emission System Vent Control Circuit
P0447 Evaporative Emission System Vent Control Circuit Open
P0448 Evaporative Emission System Vent Control Circuit Shorted
P0449 Evaporative Emission System Vent Valve/Solenoid Circuit
P0450 Evaporative Emission System Pressure Sensor/Switch
P0451 Evaporative Emission System Pressure Sensor/Switch Range/Performance
P0452 Evaporative Emission System Pressure Sensor/Switch Low
P0453 Evaporative Emission System Pressure Sensor/Switch High
P0454 Evaporative Emission System Pressure Sensor/Switch Intermittent
P0455 Evaporative Emission System Leak Detected (large leak)
P0456 Evaporative Emission System Leak Detected (very small leak)
P0457 Evaporative Emission System Leak Detected (fuel cap loose/off)
P0458 Evaporative Emission System Purge Control Valve Circuit Low
P0459 Evaporative Emission System Purge Control Valve Circuit High
P0460 Fuel Level Sensor "A" Circuit
P0461 Fuel Level Sensor "A" Circuit Range/Performance
P0462 Fuel Level Sensor "A" Circuit Low
P0463 Fuel Level Sensor "A" Circuit High
P0464 Fuel Level Sensor "A" Circuit Intermittent
P0465 EVAP Purge Flow Sensor Circuit
P0466 EVAP Purge Flow Sensor Circuit Range/Performance
P0467 EVAP Purge Flow Sensor Circuit Low
P0468 EVAP Purge Flow Sensor Circuit High
P0469 EVAP Purge Flow Sensor Circuit Intermittent
P0470 Exhaust Pressure Sensor
P0471 Exhaust Pressure Sensor Range/Performance
P0472 Exhaust Pressure Sensor Low
P0473 Exhaust Pressure Sensor High
P0474 Exhaust Pressure Sensor Intermittent
P0475 Exhaust Pressure Control Valve
P0476 Exhaust Pressure Control Valve Range/Performance
P0477 Exhaust Pressure Control Valve Low
P0478 Exhaust Pressure Control Valve High
P0479 Exhaust Pressure Control Valve Intermittent
P0480 Fan 1 Control Circuit
P0481 Fan 2 Control Circuit
P0482 Fan 3 Control Circuit
P0483 Fan Rationality Check
P0484 Fan Circuit Over Current
P0485 Fan Power/Ground Circuit
P0486 Exhaust Gas Recirculation Sensor "B" Circuit
P0487 Exhaust Gas Recirculation Throttle Position Control Circuit
P0488 Exhaust Gas Recirculation Throttle Position Control Range/Performance
P0489 Exhaust Gas Recirculation Control Circuit Low
P0490 Exhaust Gas Recirculation Control Circuit High
P0491 Secondary Air Injection System Insufficient Flow Bank 1
P0492 Secondary Air Injection System Insufficient Flow Bank 2
P0493 Fan Overspeed
P0494 Fan Speed Low
P0495 Fan Speed High
P0496 Evaporative Emission System High Purge Flow
P0497 Evaporative Emission System Low Purge Flow
P0498 Evaporative Emission System Vent Valve Control Circuit Low
P0499 Evaporative Emission System Vent Valve Control Circuit High
