Diagnostic library

Find an OBD2 code

Search the code from your scanner, then narrow the library by system, severity, or code family.

9,253 diagnostic guides

Sort

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.

Engine Problems Check soon Clear all

Quick browse

Choose a vehicle system

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

FiltersSeverity · family

Severity

All severities9253 Low priority305 Check soon8256 Urgent621

Code family

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

Vehicle coverage

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

Diagnostic codes

Showing 793–816 of 987

Most searched first

P2DF8Coolant Pump E UnderspeedCheck soonEngine Problems30–120 minutes for initial diagnosisP2DF8 relates to coolant pump e underspeed. Check the fault conditions and vehicle-specific procedure before replacing parts.P2DF9Coolant Pump E Stuck/StalledCheck soonEngine Problems30–120 minutes for initial diagnosisP2DF9 relates to coolant pump e stuck/stalled. Check the fault conditions and vehicle-specific procedure before replacing parts.P2DFBCoolant Pump E Control Module OvertemperatureCheck soonEngine Problems30–120 minutes for initial diagnosisP2DFB relates to coolant pump e control module overtemperature. Check the fault conditions and vehicle-specific procedure before replacing parts.P2E41Hybrid/EV Electronics Coolant Pump B Control Circuit/OpenCheck soonEngine Problems30–120 minutes for initial diagnosisP2E41 relates to hybrid/ev electronics coolant pump b control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P2E42Hybrid/EV Electronics Coolant Pump B PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP2E42 relates to hybrid/ev electronics coolant pump b performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2E43Hybrid/EV Electronics Coolant Pump B Control Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP2E43 relates to hybrid/ev electronics coolant pump b control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2E44Hybrid/EV Electronics Coolant Pump B Control Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP2E44 relates to hybrid/ev electronics coolant pump b control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2E45Hybrid/EV Electronics Coolant Pump B Enable CircuitCheck soonEngine Problems30–120 minutes for initial diagnosisP2E45 relates to hybrid/ev electronics coolant pump b enable circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2E47Hybrid/EV Electronics Coolant Pump B UnderspeedCheck soonEngine Problems30–120 minutes for initial diagnosisP2E47 relates to hybrid/ev electronics coolant pump b underspeed. Check the fault conditions and vehicle-specific procedure before replacing parts.P2E49Hybrid/EV Electronics Coolant Pump B Stuck/StalledCheck soonEngine Problems30–120 minutes for initial diagnosisP2E49 relates to hybrid/ev electronics coolant pump b stuck/stalled. Check the fault conditions and vehicle-specific procedure before replacing parts.P2E62Engine Coolant Bypass Valve E Control Circuit/OpenCheck soonEngine Problems30–120 minutes for initial diagnosisP2E62 relates to engine coolant bypass valve e control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P2E63Engine Coolant Bypass Valve E Control Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP2E63 relates to engine coolant bypass valve e control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2E64Engine Coolant Bypass Valve E Control Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP2E64 relates to engine coolant bypass valve e control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2E65Engine Coolant Bypass Valve E Stuck/OpenCheck soonEngine Problems30–120 minutes for initial diagnosisP2E65 relates to engine coolant bypass valve e stuck/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P2E66Engine Coolant Bypass Valve E Range/PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP2E66 relates to engine coolant bypass valve e range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2E67Engine Coolant Bypass Valve E Stuck ClosedCheck soonEngine Problems30–120 minutes for initial diagnosisP2E67 relates to engine coolant bypass valve e stuck closed. Check the fault conditions and vehicle-specific procedure before replacing parts.P2E68System Too Lean During Cylinder Deactivation Bank 1Check soonEngine Problems30–120 minutes for initial diagnosisP2E68 relates to system too lean during cylinder deactivation bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2E69System Too Rich During Cylinder Deactivation Bank 1Check soonEngine Problems30–120 minutes for initial diagnosisP2E69 relates to system too rich during cylinder deactivation bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2E6ASystem Too Lean During Cylinder Deactivation Bank 2Check soonEngine Problems30–120 minutes for initial diagnosisP2E6A relates to system too lean during cylinder deactivation bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2E6BSystem Too Rich During Cylinder Deactivation Bank 2Check soonEngine Problems30–120 minutes for initial diagnosisP2E6B relates to system too rich during cylinder deactivation bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2E79Hybrid/EV Electronics Coolant Pump C PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP2E79 relates to hybrid/ev electronics coolant pump c performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2E81Cold Start Engine Coolant Bypass Valve D Stuck ClosedCheck soonEngine Problems30–120 minutes for initial diagnosisP2E81 relates to cold start engine coolant bypass valve d stuck closed. Check the fault conditions and vehicle-specific procedure before replacing parts.P3401Cylinder 1 Deactivation/Intake Valve Control Circuit/OpenCheck soonEngine Problems30–120 minutes for initial diagnosisP3401 relates to cylinder 1 deactivation/intake valve control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P3402Cylinder 1 Deactivation/Intake Valve Control Circuit PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP3402 relates to cylinder 1 deactivation/intake valve control circuit performance. Check the fault conditions and vehicle-specific procedure before replacing parts.