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.

P1876 — P1876 — Transmission Mechanical Transfer Case 4x4 Switch Circuit Short To Battery. A fault in the automatic transmission control. Short, gentle driving to a shop is usually possible. Typical causes: valve body wear, low or degraded transmission fluid, failed shift or pressure control solenoid.
P1877 — P1877 — Transmission Mechanical 4-Wheel Drive Axle Lock Lamp Circuit Failure. A fault in the automatic transmission control. Short, gentle driving to a shop is usually possible. Typical causes: internal mechanical wear (clutches, torque converter), valve body wear, wiring or connector faults in the valve body harness.
P1878 — P1878 — Transmission Mechanical 4-Wheel Drive Axle Lock Lamp Circuit Short To Battery. A fault in the automatic transmission control. Short, gentle driving to a shop is usually possible. Typical causes: valve body wear, wiring or connector faults in the valve body harness, internal mechanical wear (clutches, torque converter).
P1879 — OBD2 code P1879 flags a problem with the automatic transmission control (transmission automatic hall effect sensor power circuit failure). Short, gentle driving to a shop is usually possible. Common culprits: internal mechanical wear (clutches, torque converter), valve body wear, failed shift or pressure control solenoid.
P1880 — Transmission Automatic Hall Effect Sensor Power Circuit Short To Battery / 4WD Low Switch Circuit Electrical (P1880): a powertrain (engine/transmission) fault affecting the automatic transmission control. Short, gentle driving to a shop is usually possible. Most often caused by valve body wear, faulty transmission speed sensor, failed shift or pressure control solenoid.
P1881 — Transmission Transfer Case 2-Wheel Drive Solenoid Circuit Failure (P1881): a powertrain (engine/transmission) fault affecting the automatic transmission control. Short, gentle driving to a shop is usually possible. Most often caused by failed shift or pressure control solenoid, wiring or connector faults in the valve body harness, faulty transmission speed sensor.
P1882 — OBD2 code P1882 flags a problem with the automatic transmission control (transmission transfer case 2-wheel drive solenoid circuit short to battery). Short, gentle driving to a shop is usually possible. Common culprits: wiring or connector faults in the valve body harness, low or degraded transmission fluid, failed shift or pressure control solenoid.
P1883 — OBD2 code P1883 flags a problem with the automatic transmission control (transmission transfer case disengaged solenoid circuit failure). Short, gentle driving to a shop is usually possible. Common culprits: internal mechanical wear (clutches, torque converter), low or degraded transmission fluid, valve body wear.
P1884 — P1884 — Transmission Transfer Case Disengaged Solenoid Open Circuit. A fault in the automatic transmission control. Short, gentle driving to a shop is usually possible. Typical causes: valve body wear, faulty transmission speed sensor, internal mechanical wear (clutches, torque converter).
P1885 — P1885 — Transmission Transfer Case Disengaged Solenoid Short to Battery. A fault in the automatic transmission control. Short, gentle driving to a shop is usually possible. Typical causes: faulty transmission speed sensor, internal mechanical wear (clutches, torque converter), failed shift or pressure control solenoid.
P1886 — OBD2 code P1886 flags a problem with the engine cooling and temperature control (engine coolant level switch circuit failure). Short, gentle driving to a shop is usually possible. Common culprits: wiring faults in the sensor circuit, low coolant level or air in the system, faulty coolant temperature sensor.
P1887 — P1887 — Four-Wheel-Drive Solenoid Circuit Fault. The vehicle can generally be driven cautiously in two-wheel drive if the transfer case shifts smoothly.
P1889 — P1889 — Oil Pump Efficiency Below Threshold. If the oil level is correct and no oil-pressure warning, knocking, or severe noise is present, drive cautiously and arrange prompt diagnosis.
P1890 — P1890 — Engine Coolant Level Switch Circuit Short to Ground. A fault in the engine cooling and temperature control. Short, gentle driving to a shop is usually possible. Typical causes: wiring faults in the sensor circuit, thermostat stuck open or closed, faulty coolant temperature sensor.
P1891 — OBD2 code P1891 flags a problem with the engine cooling and temperature control (engine coolant level switch circuit failure). Short, gentle driving to a shop is usually possible. Common culprits: low coolant level or air in the system, water pump or radiator issues, thermostat stuck open or closed.
P1892 — P1892 — 4X4 Mechanical Lock Output Circuit Failure. P1892 can prevent proper 4X4 mechanical engagement.
P1893 — P1893 — 4X4 Lock Output Short to Positive. P1893 can leave the 4X4 mechanical-lock circuit or actuator in an incorrect state.
P1894 — P1894 — Axle Disengage Solenoid Supply Overvoltage. P1894 can leave the axle disengaged when traction is required.
P1896 — P1896 — Axle Disengage Solenoid High Voltage. P1896 is not automatically a stop condition, but an incorrect axle state can bind the drivetrain or prevent the intended drive mode from engaging.
P1897 — P1897 — Axle Disengage ON Sensor Low Voltage. P1897 concerns low voltage in the axle-disengage ON position-sensor circuit.
P1898 — P1898 — Axle Disengage Lamp Supply Overvoltage. P1898 identifies excessive voltage in the axle disengage lamp circuit; it does not by itself prove that the axle has physically disengaged.
P1899 — P1899 — Axle Disengage Lamp Supply Voltage Too Low. P1899 is primarily an indicator-circuit fault, so it does not by itself prove that the axle is mechanically disengaged.
P1900 — P1900 — Engine Coolant Level Lamp Circuit Short to Ground. A fault in the engine cooling and temperature control. Short, gentle driving to a shop is usually possible. Typical causes: water pump or radiator issues, wiring faults in the sensor circuit, low coolant level or air in the system.
P1901 — P1901 — Transmission Transfer Case Disengaged Solenoid Short to Ground. A fault in the automatic transmission control. Short, gentle driving to a shop is usually possible. Typical causes: internal mechanical wear (clutches, torque converter), failed shift or pressure control solenoid, wiring or connector faults in the valve body harness.