Diagnostic library
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Search the code from your scanner, then narrow the library by system, severity, or code family.
9,253 diagnostic guides
Find codes by symptomChoose what you notice to search matching code guides.
Rough idle or shakingVibration while stoppedHard to startLong cranking or no-startEngine stallsCuts out at idle or on the roadHesitates or loses powerSlow response when acceleratingBattery light is onCharging system warningHarsh 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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These are generic OBD2 definitions. Exact make, model, engine, and year compatibility will appear after vehicle-fitment data is added.
Diagnostic codes
Showing 4705–4728 of 6682
P26B6Fuel Shutoff Valve B Control Circuit Stuck OnCheck soonFuel System30–120 minutes for initial diagnosisP26B7Engine Coolant Bypass Valve C Control Circuit/OpenCheck soonEngine Problems30–120 minutes for initial diagnosisP26B8Engine Coolant Bypass Valve C Control Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP26B9Engine Coolant Bypass Valve C Control Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP26BAEngine Coolant Bypass Valve C Stuck/OpenCheck soonEngine Problems30–120 minutes for initial diagnosisP26BBEngine Coolant Bypass Valve C Range/PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP26BCEngine Coolant Bypass Valve C Stuck ClosedCheck soonEngine Problems30–120 minutes for initial diagnosisP26BDEngine Coolant Bypass Valve D Control Circuit/OpenCheck soonEngine Problems30–120 minutes for initial diagnosisP26BEEngine Coolant Bypass Valve D Control Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP26BFEngine Coolant Bypass Valve D Control Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP26C0Engine Coolant Bypass Valve D Stuck/OpenCheck soonEngine Problems30–120 minutes for initial diagnosisP26C1Engine Coolant Bypass Valve D Range/PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP26C2Engine Coolant Bypass Valve D Stuck ClosedCheck soonEngine Problems30–120 minutes for initial diagnosisP26C3Internal Control Module Transmission Range Sensor PerformanceCheck soonTransmission Issues30–120 minutes for initial diagnosisP26C4Internal Control Module Clutch Pedal PerformanceCheck soonTransmission Issues30–120 minutes for initial diagnosisP26C5Exhaust Flow Control Valve A Control Circuit/OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP26C6Exhaust Flow Control Valve A Control Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP26C7Exhaust Flow Control Valve A Control Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP26C8Chassis Control Module 1 Requested MIL IlluminationCheck soonSensors & Electronics30–120 minutes for initial diagnosisP26C9Chassis Control Module 2 Requested MIL IlluminationCheck soonSensors & Electronics30–120 minutes for initial diagnosisP26CAEngine Coolant Pump Control Circuit/OpenCheck soonEngine Problems30–120 minutes for initial diagnosisP26CBEngine Coolant Pump Performance/Stuck OffCheck soonEngine Problems30–120 minutes for initial diagnosisP26CCEngine Coolant Pump Control Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP26CDEngine Coolant Pump Control Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosis