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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.

Check soon P · Powertrain Clear all

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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 4009–4032 of 6682

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P23B4NOx Sensor Heater Sense Circuit Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP23B4 relates to nox sensor heater sense circuit bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P23B5NOx Sensor Heater Sense Circuit Range/Performance Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP23B5 relates to nox sensor heater sense circuit range/performance bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P23B6NOx Sensor Supply Voltage Circuit Bank 1 Sensor 3Check soonElectrical & Charging System30–120 minutes for initial diagnosisP23B6 relates to nox sensor supply voltage circuit bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P23B7NOx Sensor Heater Control Circuit Range/Performance Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP23B7 relates to nox sensor heater control circuit range/performance bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P23B8NOx Sensor Heater Sense Circuit Low Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP23B8 relates to nox sensor heater sense circuit low bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P23B9NOx Sensor Heater Sense Circuit High Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP23B9 relates to nox sensor heater sense circuit high bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P23BANOx Sensor Heater Sense Circuit Intermittent Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP23BA relates to nox sensor heater sense circuit intermittent bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P23BBNOx Sensor Heater Resistance Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP23BB relates to nox sensor heater resistance bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P23BCNOx Sensor Calibration Memory Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP23BC relates to nox sensor calibration memory bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P23BDNOx Sensor Performance - Signal Biased/Stuck High Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP23BD relates to nox sensor performance - signal biased/stuck high bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P23BENOx Sensor Performance - Signal Biased/Stuck Low Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP23BE relates to nox sensor performance - signal biased/stuck low bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P23BFNOx Sensor Performance - Slow Response Low to High Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP23BF relates to nox sensor performance - slow response low to high bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P23C0NOx Sensor Performance - Slow Response High to Low Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP23C0 relates to nox sensor performance - slow response high to low bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P23C1NOx Sensor Performance - Sensing Element Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP23C1 relates to nox sensor performance - sensing element bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P23C2NOx Sensor Delayed Response - High to Low Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP23C2 relates to nox sensor delayed response - high to low bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P23C3Engine Coolant Bypass Valve C Position Sensor CircuitCheck soonEngine Problems30–120 minutes for initial diagnosisP23C3 relates to engine coolant bypass valve c position sensor circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P23C4Engine Coolant Bypass Valve C Position Sensor Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP23C4 relates to engine coolant bypass valve c position sensor circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P23C5Engine Coolant Bypass Valve C Position Sensor Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP23C5 relates to engine coolant bypass valve c position sensor circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P23C6Engine Coolant Bypass Valve C Control Circuit Driver Current/Temperature Too HighCheck soonEngine Problems30–120 minutes for initial diagnosisP23C6 relates to engine coolant bypass valve c control circuit driver current/temperature too high. Check the fault conditions and vehicle-specific procedure before replacing parts.P23C7Fuel Heater Control Module Power Control Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP23C7 relates to fuel heater control module power control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P23C8Fuel Heater Control Module Power Control Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP23C8 relates to fuel heater control module power control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P23C9Fuel Heater Control Module Power Control Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP23C9 relates to fuel heater control module power control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P23CAFuel Rail Heater Control Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP23CA relates to fuel rail heater control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P23CBFuel Rail Heater Control Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP23CB relates to fuel rail heater control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.