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
P1374
Crankshaft Position / Ignition Coil Cylinder 4 Early Activation Fault
BMW
Ignition System
High severity
P1386
Control Module Self-test, Knock Control Baseline Test Bank 1
BMW
Ignition System
High severity
P1400
Heated Catalyst Battery Voltage or Current too Low During Heating Bank 1
BMW
Auxiliary Emissions Control
Medium severity
P1402
Heated Catalyst Power Switch Over temperature Condition Bank 1
BMW
Auxiliary Emissions Control
Medium severity
P1405
Heated Catalyst Power Switch Over temperature Condition Bank 2
BMW
Auxiliary Emissions Control
Medium severity
P1406
Heated Catalyst Internal Control Module Checksum/ROM Error
BMW
Auxiliary Emissions Control
Medium severity
P1413
Secondary Air Injection Pump Relay Control Circuit Signal Low
BMW
Auxiliary Emissions Control
Medium severity
P1419
Secondary Air System Air Mass Flow Sensor Disconnected or Stuck Signal
BMW
Auxiliary Emissions Control
Medium severity
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