OBD2 Fault Code Library

Free lookup for thousands of OBD2 trouble codes: filter by family, read short meanings, and open deeper articles. Desktop ELM327 scanner with live data and AI guidance.

OBD2 symptoms

Look up diagnostic trouble codes by what the car is doing: misfire, overheating, rough idle, a check engine light, and other common symptoms.

P1102 — 1-4 Upshift (Skip Shift) Solenoid Control Circuit Malfunction (P1102): a powertrain (engine/transmission) fault affecting the sensor and actuator circuits. The car is usually drivable while you plan the repair. Most often caused by corroded, loose or damaged connector, control module driver fault, blown fuse feeding the circuit.
P1103 — 1-4 Upshift (Skip Shift) Lamp Control Circuit Malfunction (P1103): a powertrain (engine/transmission) fault affecting the sensor and actuator circuits. The car is usually drivable while you plan the repair. Most often caused by corroded, loose or damaged connector, blown fuse feeding the circuit, control module driver fault.
P1105 — MAF Sensor Out Of Self Test Range./ (P1105): a powertrain (engine/transmission) fault affecting the throttle and intake air metering. Short, gentle driving to a shop is usually possible. Most often caused by wiring or connector faults in the throttle circuit, faulty throttle position sensor or pedal sensor, contaminated or failed MAF/MAP sensor.
P1106 — P1106 — KOER Not Able To Complete KOER Aborted. A fault in the sensor and actuator circuits. The car is usually drivable while you plan the repair. Typical causes: poor ground connection, faulty sensor or actuator of the affected circuit, control module driver fault.
P1107 — P1107 — MAF Sensor In Range But Lower Than Expected. A fault in the throttle and intake air metering. Short, gentle driving to a shop is usually possible. Typical causes: faulty throttle position sensor or pedal sensor, intake air leaks after the MAF sensor, failed electronic throttle motor.
P1108 — P1108 — MAF Sensor In Range But Higher Than Expected. A fault in the throttle and intake air metering. Short, gentle driving to a shop is usually possible. Typical causes: intake air leaks after the MAF sensor, wiring or connector faults in the throttle circuit, dirty throttle body or stuck throttle plate.
P1109 — MAF Ground Malfunction (P1109): a powertrain (engine/transmission) fault affecting the throttle and intake air metering. Short, gentle driving to a shop is usually possible. Most often caused by failed electronic throttle motor, contaminated or failed MAF/MAP sensor, faulty throttle position sensor or pedal sensor.
P1110 — Dual Alternator Upper Fault (P1110): a powertrain (engine/transmission) fault affecting the sensor and actuator circuits. The car is usually drivable while you plan the repair. Most often caused by blown fuse feeding the circuit, poor ground connection, open or shorted wiring in the circuit.
P1113 — OBD2 code P1113 flags a problem with the sensor and actuator circuits (dual alternator battery lamp circuit malfunction). The car is usually drivable while you plan the repair. Common culprits: control module driver fault, faulty sensor or actuator of the affected circuit, open or shorted wiring in the circuit.
P1114 — OBD2 code P1114 flags a problem with the sensor and actuator circuits (IAT - b sensor intermittent). The car is usually drivable while you plan the repair. Common culprits: blown fuse feeding the circuit, corroded, loose or damaged connector, faulty sensor or actuator of the affected circuit.
P1115 — IAT Sensor (D/C) Open/Short (P1115): a powertrain (engine/transmission) fault affecting the sensor and actuator circuits. The car is usually drivable while you plan the repair. Most often caused by blown fuse feeding the circuit, control module driver fault, open or shorted wiring in the circuit.
P1116 — OBD2 code P1116 flags a problem with the throttle and intake air metering (intake air temperature (IAT) sensor circuit intermittent high voltage). Short, gentle driving to a shop is usually possible. Common culprits: dirty throttle body or stuck throttle plate, wiring or connector faults in the throttle circuit, faulty throttle position sensor or pedal sensor.
P1117 — OBD2 code P1117 flags a problem with the throttle and intake air metering (intake air temperature (IAT) sensor circuit intermittent low voltage). Short, gentle driving to a shop is usually possible. Common culprits: faulty throttle position sensor or pedal sensor, intake air leaks after the MAF sensor, wiring or connector faults in the throttle circuit.
P1118 — OBD2 code P1118 flags a problem with the sensor and actuator circuits (IAT sensor open/short). The car is usually drivable while you plan the repair. Common culprits: blown fuse feeding the circuit, poor ground connection, corroded, loose or damaged connector.
P1121 — Engine Coolant sensor out of range/ECT Sensor Out Of Self Test Range (P1121): a powertrain (engine/transmission) fault affecting the engine cooling and temperature control. Short, gentle driving to a shop is usually possible. Most often caused by low coolant level or air in the system, water pump or radiator issues, wiring faults in the sensor circuit.
P1122 — Engine Coolant Sensor intermittent/ECT Sensor Intermittent (P1122): a powertrain (engine/transmission) fault affecting the engine cooling and temperature control. Short, gentle driving to a shop is usually possible. Most often caused by faulty coolant temperature sensor, water pump or radiator issues, thermostat stuck open or closed.
P1123 — OBD2 code P1123 flags a problem with the sensor and actuator circuits (manifold absolute temperature circuit low input). The car is usually drivable while you plan the repair. Common culprits: corroded, loose or damaged connector, open or shorted wiring in the circuit, control module driver fault.
P1124 — Manifold Absolute Temperature Circuit High Input (P1124): a powertrain (engine/transmission) fault affecting the sensor and actuator circuits. The car is usually drivable while you plan the repair. Most often caused by poor ground connection, open or shorted wiring in the circuit, corroded, loose or damaged connector.
P1125 — Throttle position sensor out of range (P1125): a powertrain (engine/transmission) fault affecting the throttle and intake air metering. Short, gentle driving to a shop is usually possible. Most often caused by faulty throttle position sensor or pedal sensor, dirty throttle body or stuck throttle plate, contaminated or failed MAF/MAP sensor.
P1126 — P1126 — Throttle Position (TP) Sensor Circuit Intermittent High Voltage. A fault in the throttle and intake air metering. Short, gentle driving to a shop is usually possible. Typical causes: wiring or connector faults in the throttle circuit, intake air leaks after the MAF sensor, faulty throttle position sensor or pedal sensor.
P1127 — Throttle Position (TP) Sensor Circuit Intermittent Low Voltage (P1127): a powertrain (engine/transmission) fault affecting the throttle and intake air metering. Short, gentle driving to a shop is usually possible. Most often caused by contaminated or failed MAF/MAP sensor, faulty throttle position sensor or pedal sensor, intake air leaks after the MAF sensor.
P1128 — OBD2 code P1128 flags a problem with the throttle and intake air metering (throttle position sensor in range but higher than expected). Short, gentle driving to a shop is usually possible. Common culprits: dirty throttle body or stuck throttle plate, wiring or connector faults in the throttle circuit, intake air leaks after the MAF sensor.
P1129 — P1129 — Throttle Position Sensor Out Of Self Test Range. A fault in the throttle and intake air metering. Short, gentle driving to a shop is usually possible. Typical causes: contaminated or failed MAF/MAP sensor, faulty throttle position sensor or pedal sensor, failed electronic throttle motor.
P1130 — P1130 — Throttle position sensor intermittent. A fault in the throttle and intake air metering. Short, gentle driving to a shop is usually possible. Typical causes: failed electronic throttle motor, wiring or connector faults in the throttle circuit, intake air leaks after the MAF sensor.