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
P1029
Intake Manifold Air Control Valve Position Sensor Upper Limit Not Reached
Mercedes Benz
Fuel and Air Metering
High severity
P1032
Air Fuel Ratio Sensor 1 Heater Control Circuit High Bank 1
Mercedes Benz
Fuel and Air Metering
High severity
P1033
Nitrogen Oxides Sensor Signal Too Low
Mercedes Benz
Auxiliary Emissions Control
Medium severity
P1034
Nitrogen Oxides Sensor Signal Outside Tolerance
Mercedes Benz
Auxiliary Emissions Control
Medium severity
P1035
Nitrogen Oxides Sensor Range Performance Problem
Mercedes Benz
Auxiliary Emissions Control
Medium severity
P1036
Nitrogen Oxides Sensor Short To Positive
Mercedes Benz
Auxiliary Emissions Control
Medium severity
P1037
Nitrogen Oxides Sensor Short To Ground
Mercedes Benz
Auxiliary Emissions Control
Medium severity
P1039
Vehicle Speed Signal Missing or Improper
Mercedes Benz
Vehicle Speed and Idle Control System
High severity
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