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Rough idle or shakingVibration while stopped Hard to startLong cranking or no-start Engine stallsCuts out at idle or on the road Hesitates or loses powerSlow response when accelerating Battery light is onCharging system warning Harsh gear changesDelayed or rough shifting

A symptom can have several causes. Treat matching codes as clues and follow the diagnostic checks in each guide.

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Engine1049 Emissions515 Fuel1016 Sensors & Electronics2110 Transmission866 Electrical & Charging1797 Body & Restraints193 Chassis & Brakes479 Network & Communication1228

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All severities9253 Low priority305 Check soon8256 Urgent621

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All families9253 P · Powertrain7353 B · Body193 C · Chassis479 U · Network1228

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Diagnostic codes

Showing 241–264 of 7353

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P0126Insufficient Coolant Temperature for Stable OperationCheck soonEngine Problems30–120 minutes for initial diagnosisP0126 relates to insufficient coolant temperature for stable operation. Check the fault conditions and vehicle-specific procedure before replacing parts.P0127Intake Air Temperature Too HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0127 relates to intake air temperature too high. Check the fault conditions and vehicle-specific procedure before replacing parts.P0129Barometric Pressure Too LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0129 relates to barometric pressure too low. Check the fault conditions and vehicle-specific procedure before replacing parts.P012ATurbocharger/Supercharger Inlet Pressure Sensor A CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP012A relates to turbocharger/supercharger inlet pressure sensor a circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P012BTurbocharger/Supercharger Inlet Pressure Sensor A Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP012B relates to turbocharger/supercharger inlet pressure sensor a circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P012CTurbocharger/Supercharger Inlet Pressure Sensor A Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP012C relates to turbocharger/supercharger inlet pressure sensor a circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P012DTurbocharger/Supercharger Inlet Pressure Sensor A Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP012D relates to turbocharger/supercharger inlet pressure sensor a circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P012ETurbocharger/Supercharger Inlet Pressure Sensor A Circuit Intermittent/ErraticCheck soonSensors & Electronics30–120 minutes for initial diagnosisP012E relates to turbocharger/supercharger inlet pressure sensor a circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P012FEngine Coolant Temperature / Engine Oil Temperature CorrelationCheck soonEngine Problems30–120 minutes for initial diagnosisP012F relates to engine coolant temperature / engine oil temperature correlation. Check the fault conditions and vehicle-specific procedure before replacing parts.P0131O2 Sensor Low Voltage Bank 1 Sensor 1Sensors & ElectronicsDiagnose P0131 oxygen sensor low voltage code. Learn why the upstream O2 sensor is reading low and how to fix it.P0132O2 Sensor Circuit High Voltage Bank 1 Sensor 1Sensors & ElectronicsDiagnose the P0132 high-voltage oxygen sensor code on Bank 1 Sensor 1, including a rich-condition check and sensor testing.P0133O2 Sensor Slow Response Bank 1 Sensor 1Sensors & ElectronicsFix P0133 slow responding oxygen sensor. Learn why the O2 sensor is responding slowly and repair options.P0134O2 Sensor No Activity Detected Bank 1 Sensor 1Sensors & ElectronicsUnderstand the P0134 inactive oxygen sensor code, why the ECM sees no signal, and how to test the heater and signal circuits.P0135O2 Sensor Heater Circuit Malfunction Bank 1 Sensor 1Sensors & ElectronicsDiagnose P0135 oxygen sensor heater code. Learn about the upstream O2 sensor heater circuit and repair options.P0136Oxygen Sensor Circuit Bank 1 Sensor 2Low prioritySensors & Electronics30–90 minutes for initial diagnosisP0136 means Oxygen Sensor Circuit Bank 1 Sensor 2. Learn the likely symptoms, common causes, and a safe diagnostic order before replacing parts.P013AO2 Sensor Slow Response - Rich to Lean Bank 1 Sensor 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP013A relates to o2 sensor slow response - rich to lean bank 1 sensor 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P013BO2 Sensor Slow Response - Lean to Rich Bank 1 Sensor 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP013B relates to o2 sensor slow response - lean to rich bank 1 sensor 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P013CO2 Sensor Slow Response - Rich to Lean Bank 2 Sensor 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP013C relates to o2 sensor slow response - rich to lean bank 2 sensor 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P013DO2 Sensor Slow Response - Lean to Rich Bank 2 Sensor 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP013D relates to o2 sensor slow response - lean to rich bank 2 sensor 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P013EO2 Sensor Delayed Response - Rich to Lean Bank 1 Sensor 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP013E relates to o2 sensor delayed response - rich to lean bank 1 sensor 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P013FO2 Sensor Delayed Response - Lean to Rich Bank 1 Sensor 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP013F relates to o2 sensor delayed response - lean to rich bank 1 sensor 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P0140Oxygen Sensor Circuit No Activity Detected Bank 1 Sensor 2Low prioritySensors & Electronics30–90 minutes for initial diagnosisP0140 means Oxygen Sensor Circuit No Activity Detected Bank 1 Sensor 2. Learn the likely symptoms, common causes, and a safe diagnostic order before replacing parts.P0141O2 Sensor Heater Circuit Bank 1 Sensor 2Sensors & ElectronicsDiagnose P0141 oxygen sensor heater code. Learn about the downstream O2 sensor heater circuit and repair options.P0142Oxygen Sensor Circuit Bank 1 Sensor 3Check soonEmissions System45–120 minutes for initial diagnosisP0142 means Oxygen Sensor Circuit Bank 1 Sensor 3. Learn the likely symptoms, causes, safety implications, and a practical diagnostic order.