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Find codes by symptomChoose what you notice to search matching code guides.

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 1369–1392 of 8256

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P0544Exhaust Gas Temperature Sensor Circuit Bank 1 Sensor 1Check soonEmissions System30–120 minutes for initial diagnosisP0544 indicates a fault related to exhaust gas temperature sensor circuit bank 1 sensor 1. Learn the likely causes and a practical diagnostic order before replacing parts.P0545Exhaust Gas Temperature Sensor Circuit Low Bank 1 Sensor 1Check soonEmissions System30–120 minutes for initial diagnosisP0545 relates to exhaust gas temperature sensor circuit low bank 1 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P0546Exhaust Gas Temperature Sensor Circuit High Bank 1 Sensor 1Check soonEmissions System30–120 minutes for initial diagnosisP0546 relates to exhaust gas temperature sensor circuit high bank 1 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P0547Exhaust Gas Temperature Sensor Circuit Bank 2 Sensor 1Check soonEmissions System30–120 minutes for initial diagnosisP0547 relates to exhaust gas temperature sensor circuit bank 2 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P0548Exhaust Gas Temperature Sensor Circuit Low Bank 2 Sensor 1Check soonEmissions System30–120 minutes for initial diagnosisP0548 relates to exhaust gas temperature sensor circuit low bank 2 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P0549Exhaust Gas Temperature Sensor Circuit High Bank 2 Sensor 1Check soonEmissions System30–120 minutes for initial diagnosisP0549 relates to exhaust gas temperature sensor circuit high bank 2 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P054ACold Start B Camshaft Position Timing Over-Advanced Bank 1Check soonEngine Problems30–120 minutes for initial diagnosisP054A relates to cold start b camshaft position timing over-advanced bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P054BCold Start B Camshaft Position Timing Over-Retarded Bank 1Check soonEngine Problems30–120 minutes for initial diagnosisP054B relates to cold start b camshaft position timing over-retarded bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P054CCold Start B Camshaft Position Timing Over-Advanced Bank 2Check soonEngine Problems30–120 minutes for initial diagnosisP054C relates to cold start b camshaft position timing over-advanced bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P054DCold Start B Camshaft Position Timing Over-Retarded Bank 2Check soonEngine Problems30–120 minutes for initial diagnosisP054D relates to cold start b camshaft position timing over-retarded bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P054EIdle Control System - Fuel Quantity Lower Than ExpectedCheck soonFuel System30–120 minutes for initial diagnosisP054E relates to idle control system - fuel quantity lower than expected. Check the fault conditions and vehicle-specific procedure before replacing parts.P054FIdle Control System - Fuel Quantity Higher Than ExpectedCheck soonFuel System30–120 minutes for initial diagnosisP054F relates to idle control system - fuel quantity higher than expected. Check the fault conditions and vehicle-specific procedure before replacing parts.P0555Brake Booster Pressure Sensor CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0555 relates to brake booster pressure sensor circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P0556Brake Booster Pressure Sensor Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0556 relates to brake booster pressure sensor circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P0557Brake Booster Pressure Sensor Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0557 relates to brake booster pressure sensor circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P0558Brake Booster Pressure Sensor Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0558 relates to brake booster pressure sensor circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P0559Brake Booster Pressure Sensor Circuit IntermittentCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0559 relates to brake booster pressure sensor circuit intermittent. Check the fault conditions and vehicle-specific procedure before replacing parts.P055AEngine Oil Pressure Sensor/Switch B CircuitCheck soonEngine Problems30–120 minutes for initial diagnosisP055A relates to engine oil pressure sensor/switch b circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P055BEngine Oil Pressure Sensor/Switch B Range/PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP055B relates to engine oil pressure sensor/switch b range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P055CEngine Oil Pressure Sensor/Switch B LowCheck soonEngine Problems30–120 minutes for initial diagnosisP055C relates to engine oil pressure sensor/switch b low. Check the fault conditions and vehicle-specific procedure before replacing parts.P055DEngine Oil Pressure Sensor/Switch B HighCheck soonEngine Problems30–120 minutes for initial diagnosisP055D relates to engine oil pressure sensor/switch b high. Check the fault conditions and vehicle-specific procedure before replacing parts.P055EOxygen Sensor Control Module System VoltageCheck soonEmissions System30–120 minutes for initial diagnosisP055E relates to oxygen sensor control module system voltage. Check the fault conditions and vehicle-specific procedure before replacing parts.P055FEngine Oil Pressure Out of RangeCheck soonEngine Problems30–120 minutes for initial diagnosisP055F relates to engine oil pressure out of range. Check the fault conditions and vehicle-specific procedure before replacing parts.P0561System Voltage UnstableCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP0561 indicates a fault related to system voltage unstable. Learn the likely causes and a practical diagnostic order before replacing parts.