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.

Free on OBD DashX

Looking for real-world repair data?

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.

  • Real-world fix data
  • How often it happens
  • Step-by-step repairs
Browse codes on OBD DashX No sign-up needed · available in 10 languages
P1134 HO2S Transition Time Ratio Sensor 1
Fuel and Air Metering High severity
P1136 Fan Control Circuit Malfunction
Auxiliary Emissions Control High severity
P1137 Lack Of HO2S Switch - Sensor Indicates Lean
Fuel and Air Metering High severity
P1138 Lack Of HO2S12 Switch - Sensor Indicates Rich
Fuel and Air Metering High severity
P1140 Water In Fuel Condition
Fuel and Air Metering High severity
P1141 Fuel Restriction Indicator Circuit Malfunction
Fuel and Air Metering High severity
P1142 Fuel Restriction Condition
Fuel and Air Metering High severity
P1144 Air Assist Control Valve Circuit Malfunction
Auxiliary Emissions Control High severity
P1150 Lack Of HO2S21 Switch - Adaptive Fuel At Limit
Fuel and Air Metering Medium severity
P1152 Lack Of HO2S21 Switch - Sensor Indicates Rich
Fuel and Air Metering Medium severity
P1153 Bank 2 Fuel Control Shifted Lean
Fuel and Air Metering Medium severity
P1154 Bank 2 Fuel Control Shifted Rich
Fuel and Air Metering Medium severity
P1155 Alternative Fuel Controller
Fuel and Air Metering Medium severity
P1157 Lack Of HO2S22 Switch - Sensor Indicates Lean
Fuel and Air Metering Medium severity

Search fault codes

Scan your own car

Read and clear fault codes, live data and service resets with the CaRPM app.