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

Diagnostic codes

Showing 73–96 of 121

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P2516A/C Refrigerant Pressure Sensor B Circuit Range/PerformanceLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2516 relates to a/c refrigerant pressure sensor b circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2517A/C Refrigerant Pressure Sensor B Circuit LowLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2517 relates to a/c refrigerant pressure sensor b circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2518A/C Refrigerant Pressure Sensor B Circuit HighLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2518 relates to a/c refrigerant pressure sensor b circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2519A/C Request A CircuitLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2519 relates to a/c request a circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2520A/C Request A Circuit LowLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2520 relates to a/c request a circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2521A/C Request A Circuit HighLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2521 relates to a/c request a circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2522A/C Request B CircuitLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2522 relates to a/c request b circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2523A/C Request B Circuit LowLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2523 relates to a/c request b circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2524A/C Request B Circuit HighLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2524 relates to a/c request b circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P255FA/C Request A Circuit Range/PerformanceLow prioritySensors & Electronics30–120 minutes for initial diagnosisP255F relates to a/c request a circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2561A/C Control Module Requested MIL IlluminationLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2561 relates to a/c control module requested mil illumination. Check the fault conditions and vehicle-specific procedure before replacing parts.P256FA/C Request B Circuit Range/PerformanceLow prioritySensors & Electronics30–120 minutes for initial diagnosisP256F relates to a/c request b circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2583Cruise Control Front Distance Range Sensor Single Sensor or CenterLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2583 relates to cruise control front distance range sensor single sensor or center. Check the fault conditions and vehicle-specific procedure before replacing parts.P2591Cruise Control Front Distance Range Sensor LeftLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2591 relates to cruise control front distance range sensor left. Check the fault conditions and vehicle-specific procedure before replacing parts.P2592Cruise Control Front Distance Range Sensor RightLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2592 relates to cruise control front distance range sensor right. Check the fault conditions and vehicle-specific procedure before replacing parts.P2611A/C Refrigerant Distribution Valve A Control Circuit/OpenLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2611 relates to a/c refrigerant distribution valve a control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P2612A/C Refrigerant Distribution Valve A Control Circuit LowLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2612 relates to a/c refrigerant distribution valve a control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2613A/C Refrigerant Distribution Valve A Control Circuit HighLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2613 relates to a/c refrigerant distribution valve a control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P265FVariable A/C Compressor Control Circuit Range/PerformanceLow prioritySensors & Electronics30–120 minutes for initial diagnosisP265F relates to variable a/c compressor control circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P26FDA/C Compressor Internal Control Module PerformanceLow prioritySensors & Electronics30–120 minutes for initial diagnosisP26FD relates to a/c compressor internal control module performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2CD4A/C Refrigerant Pressure Sensor A/B CorrelationLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2CD4 relates to a/c refrigerant pressure sensor a/b correlation. Check the fault conditions and vehicle-specific procedure before replacing parts.P2E80A/C Compressor Control Module InternalTemperature Sensor B Circuit Intermittent/ErraticLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2E80 relates to a/c compressor control module internaltemperature sensor b circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P0052Heated Oxygen Sensor Heater Control Circuit High Bank 2 Sensor 1Low prioritySensors & Electronics45–120 minutes for initial diagnosisP0052 means Heated Oxygen Sensor Heater Control Circuit High Bank 2 Sensor 1. Learn the likely symptoms, causes, safety implications, and a practical diagnostic order.P0053Heated Oxygen Sensor Heater Resistance Bank 1 Sensor 1Low prioritySensors & Electronics45–120 minutes for initial diagnosisP0053 means Heated Oxygen Sensor Heater Resistance Bank 1 Sensor 1. Learn the likely symptoms, causes, safety implications, and a practical diagnostic order.