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9,253 diagnostic guides

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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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These are generic OBD2 definitions. Exact make, model, engine, and year compatibility will appear after vehicle-fitment data is added.

Diagnostic codes

Showing 121–144 of 987

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P0377Timing Reference High Resolution Signal B Too Few PulsesCheck soonEngine Problems30–120 minutes for initial diagnosisP0377 relates to timing reference high resolution signal b too few pulses. Check the fault conditions and vehicle-specific procedure before replacing parts.P0378Timing Reference High Resolution Signal B Intermittent/Erratic PulsesCheck soonEngine Problems30–120 minutes for initial diagnosisP0378 relates to timing reference high resolution signal b intermittent/erratic pulses. Check the fault conditions and vehicle-specific procedure before replacing parts.P0379Timing Reference High Resolution Signal B No PulsesCheck soonEngine Problems30–120 minutes for initial diagnosisP0379 relates to timing reference high resolution signal b no pulses. Check the fault conditions and vehicle-specific procedure before replacing parts.P037CCold Start Camshaft Profile System PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP037C relates to cold start camshaft profile system performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P0385Crankshaft Position Sensor B CircuitCheck soonEngine Problems30–120 minutes for initial diagnosisP0385 relates to crankshaft position sensor b circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P0386Crankshaft Position Sensor B Circuit Range/PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP0386 relates to crankshaft position sensor b circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P0387Crankshaft Position Sensor B Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP0387 relates to crankshaft position sensor b circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P0388Crankshaft Position Sensor B Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP0388 relates to crankshaft position sensor b circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P0389Crankshaft Position Sensor B Circuit IntermittentCheck soonEngine Problems30–120 minutes for initial diagnosisP0389 relates to crankshaft position sensor b circuit intermittent. Check the fault conditions and vehicle-specific procedure before replacing parts.P0390Camshaft Position Sensor B Circuit Bank 2Check soonEngine Problems30–120 minutes for initial diagnosisP0390 relates to camshaft position sensor b circuit bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P0391Camshaft Position Sensor B Circuit Range/Performance Bank 2Check soonEngine Problems30–120 minutes for initial diagnosisP0391 relates to camshaft position sensor b circuit range/performance bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P0392Camshaft Position Sensor B Circuit Low Bank 2Check soonEngine Problems30–120 minutes for initial diagnosisP0392 relates to camshaft position sensor b circuit low bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P0393Camshaft Position Sensor B Circuit High Bank 2Check soonEngine Problems30–120 minutes for initial diagnosisP0393 relates to camshaft position sensor b circuit high bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P0394Camshaft Position Sensor B Circuit Intermittent Bank 2Check soonEngine Problems30–120 minutes for initial diagnosisP0394 relates to camshaft position sensor b circuit intermittent bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P0395Cylinder 1 Pressure Sensor CircuitCheck soonEngine Problems30–120 minutes for initial diagnosisP0395 relates to cylinder 1 pressure sensor circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P0396Cylinder 1 Pressure Sensor Circuit Range/PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP0396 relates to cylinder 1 pressure sensor circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P0397Cylinder 1 Pressure Sensor Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP0397 relates to cylinder 1 pressure sensor circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P0398Cylinder 1 Pressure Sensor Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP0398 relates to cylinder 1 pressure sensor circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P0399Cylinder 1 Pressure Sensor Circuit Intermittent/ErraticCheck soonEngine Problems30–120 minutes for initial diagnosisP0399 relates to cylinder 1 pressure sensor circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P039ACylinder 1 Pressure Too LowCheck soonEngine Problems30–120 minutes for initial diagnosisP039A relates to cylinder 1 pressure too low. Check the fault conditions and vehicle-specific procedure before replacing parts.P039BCylinder 1 Pressure Too HighCheck soonEngine Problems30–120 minutes for initial diagnosisP039B relates to cylinder 1 pressure too high. Check the fault conditions and vehicle-specific procedure before replacing parts.P039CCylinder 1 Pressure Variation LowCheck soonEngine Problems30–120 minutes for initial diagnosisP039C relates to cylinder 1 pressure variation low. Check the fault conditions and vehicle-specific procedure before replacing parts.P039DCylinder 1 Pressure Variation HighCheck soonEngine Problems30–120 minutes for initial diagnosisP039D relates to cylinder 1 pressure variation high. Check the fault conditions and vehicle-specific procedure before replacing parts.P039ECylinder 1 Combustion PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP039E relates to cylinder 1 combustion performance. Check the fault conditions and vehicle-specific procedure before replacing parts.