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

U0187 Lost Communication With Digital Disc Player/Changer Module A
Communication Network System High severity
U0204 Lost Communication With Door Control Module F
Communication Network System High severity
P2502 Charging Sys Voltage
Computer Output Circuit High severity
P1929 Open circuit detected in engine coolant fan
Volkswagen Fuel and Air Metering High severity
P1930 Open circuit detected in engine coolant fan
Volkswagen Fuel and Air Metering High severity
P1931 Internal malfunction in fan control module
Volkswagen Fuel and Air Metering High severity
P1932 Issue in immobilizer
Volkswagen Computer Output Circuit High severity
P1933 Issue in throttle position sensor
Volkswagen Fuel and Air Metering High severity
P1934 Issue in radiator exhaust temperature sensor
Volkswagen Auxiliary Emissions Control High severity
P1935 Issue in radiator exhaust temperature sensor
Volkswagen Auxiliary Emissions Control High severity
P1936 Issue in battery (generator)
Volkswagen Computer Output Circuit High severity
P1937 Issue in battery (generator)
Volkswagen Computer Output Circuit High severity
P1938 Open or short circuit detected in engine coolant pump relay
Volkswagen Fuel and Air Metering High severity
P1939 Internal malfunction in Immobilizer control module
Volkswagen Computer Output Circuit High severity
P1940 Internal malfunction in Battery control module
Volkswagen Computer Output Circuit High severity

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