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Diagnostic Trouble Code numbers are read by plugging a code reader or scan tool into the vehicle diagnostic connector (usually located under the instrument panel near the steering column). The presence of a code will turn on the Check Engine Light. The light will remain on until the code has been erased. The code number does not tell you which part has failed. It only indicates a possible fault has been detected in the circuit, system or sensor described. Further testing is usually required to isolate the fault BEFORE repairs are made. For diagnostic charts and vehicle specific repair information, refer to a service manual, or the OEM technical website.
DTC CODES P0400 to P0499
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
P0416....Secondary Air Injection System Relay 'A' Circuit
P0419....Secondary Air injection System Relay 'B' Circuit
P0420....Catalyst System Efficiency Below Threshold (Bank 1) (Click Here for diagnostic help with catalytic converter codes)
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 Input (Bank 1)
P0428....Catalyst Temperature Sensor High Input (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 Input (Bank 2)
P0438....Catalyst Temperature Sensor High Input (Bank 2)
P0439....Catalyst Heater Control Circuit (Bank 2)
P0440....Evaporative Emission Control System (Click Here for help diagnosing EVAP faults )
P0441....Evaporative Emission Control System Incorrect Purge Flow
P0442....Evaporative Emission Control System Leak Detected (small leak)
P0443....Evaporative Emission Control System Purge Control Valve Circuit
P0444....Evaporative Emission Control System Purge Control Valve Circuit Open
P0445....Evaporative Emission Control System Purge Control Valve Circuit Shorted
P0446....Evaporative Emission Control System Vent Control Circuit
P0447....Evaporative Emission Control System Vent Control Circuit Open
P0448....Evaporative Emission Control System Vent Control Circuit Shorted
P0449....Evaporative Emission Control System Vent Valve/Solenoid Circuit
P0450....Evaporative Emission Control System Pressure Sensor
P0451....Evaporative Emission Control System Pressure Sensor Range/Performance
P0452....Evaporative Emission Control System Pressure Sensor Low Input
P0453....Evaporative Emission Control System Pressure Sensor High input
P0454....Evaporative Emission Control System Pressure Sensor Intermittent
P0455....Evaporative Emission Control System Leak Detected (gross leak)
P0456....Evaporative Emission Control System Leak Detected (very small leak)
P0457....Evaporative Emission Control System Leak Detected (fuel cap loose/off)
P0460....Fuel Level Sensor Circuit
P0461....Fuel Level Sensor Circuit Range/Performance
P0462....Fuel Level Sensor Circuit Low Input
P0463....Fuel Level Sensor Circuit High Input
P0464....Fuel Level Sensor Circuit Intermittent
P0465....EVAP Purge Flow Sensor Circuit
P0466....EVAP Purge Flow Sensor Circuit Range/Performance
P0467....EVAP Purge Flow Sensor Circuit Low Input
P0468....EVAP Purge Flow Sensor Circuit High Input
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....Cooling Fan 1 Control Circuit (Click Here for diagnostic help with Electric Cooling Fan problems)
P0481....Cooling Fan 2 Control Circuit
P0482....Cooling Fan 3 Control Circuit
P0483....Cooling Fan Rationality Check
P0484....Cooling Fan Circuit Over Current
P0485....Cooling Fan Power/Ground Circuit (Click Here for diagnostic help with Cooling Fan Relay problems)
P0486....Exhaust Gas Recirculation Sensor 'B' Circuit
P0487....Exhaust Gas Recirculation Throttle Position Control Circuit
P0488....Exhaust Gas Recirculation Throttle Position Control Range/Performance
P0491....Secondary Air Injection System (Bank 1)
P0492....Secondary Air Injection System (Bank 2)
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