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
P1391
Wheel Speed Sensor 1 G-Sensor Circuit Performance
Honda
Vehicle Speed and Idle Control System
High severity
P1400
Differential Pressure Feedback Electronic Sensor Circuit Low Voltage
Honda
Auxiliary Emissions Control
Medium severity
P1401
Differential Pressure Feedback Electronic Sensor Circuit High Voltage
Honda
Auxiliary Emissions Control
Medium severity
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