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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OBD DashX shows which problems come with each code, how often they show up in other vehicles, and how to fix them — step by step.
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Fault codes
P1039
Vehicle Speed Signal Missing or Improper
Ford
Vehicle Speed and Idle Control System
High severity
P1052
Air Fuel Ratio Sensor 1 Heater Control Circuit High Bank 2
Ford
Fuel and Air Metering
High severity
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