OBD fault code library
Look up any P or U code to see what it means, what causes it, the parts involved and how it gets fixed.
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Fault codes
P2423
HC Adsorption Catalyst Efficiency Below Threshold Bank1
Auxiliary Emissions Control
Medium severity
P2424
HC Adsorption Catalyst Efficiency Below Threshold Bank2
Auxiliary Emissions Control
Medium severity
P2425
Exhaust Gas Recirculation Cooling Valve Ctrl Circuit/Open
Auxiliary Emissions Control
Medium severity
P2431
Sec Air Injector Sys Air Flow/Press Sensor Circuit Range/Performance Bank1
Auxiliary Emissions Control
High severity
P2434
Sec Air Injector Sys Air Flow/Press Sensor Circuit Interim/Erratic Bank1
Auxiliary Emissions Control
High severity
P2435
Sec Air Injector Sys Air Flow/Press Sensor Circuit Bank2
Auxiliary Emissions Control
High severity
P2438
Sec Air Injector Sys Air Flow/Press Sensor Circuit High Bank2
Auxiliary Emissions Control
High severity
P2442
Sec Air Injector Sys Switching Valve Stuck Open Bank2
Auxiliary Emissions Control
High severity
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