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.

P0AFB — P0AFB — Hybrid Battery System Voltage High. A fault in the sensor and actuator circuits. The car is usually drivable while you plan the repair. Typical causes: blown fuse feeding the circuit, poor ground connection, faulty sensor or actuator of the affected circuit.
P0AFC — P0AFC — Hybrid Battery Pack Sensor Module. A fault in the sensor and actuator circuits. The car is usually drivable while you plan the repair. Typical causes: control module driver fault, faulty sensor or actuator of the affected circuit, poor ground connection.
P0AFD — OBD2 code P0AFD flags a problem with the sensor and actuator circuits (hybrid battery pack temperature too low). The car is usually drivable while you plan the repair. Common culprits: faulty sensor or actuator of the affected circuit, control module driver fault, open or shorted wiring in the circuit.
P0AFE — P0AFE — Conversion. A fault in the sensor and actuator circuits. The car is usually drivable while you plan the repair. Typical causes: open or shorted wiring in the circuit, corroded, loose or damaged connector, blown fuse feeding the circuit.
P0AFF — System Voltage Too Low for Voltage Step Down Conversion (P0AFF): 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 open or shorted wiring in the circuit, control module driver fault, poor ground connection.
P0B00 — P0B00 — Auxiliary Transmission Fluid Pump Motor Phase U Current. A fault in the automatic transmission control. Short, gentle driving to a shop is usually possible. Typical causes: failed shift or pressure control solenoid, valve body wear, low or degraded transmission fluid.
P0B01 — OBD2 code P0B01 flags a problem with the automatic transmission control (auxiliary transmission fluid pump motor phase u current low). Short, gentle driving to a shop is usually possible. Common culprits: faulty transmission speed sensor, internal mechanical wear (clutches, torque converter), failed shift or pressure control solenoid.
P0B02 — P0B02 — Auxiliary Transmission Fluid Pump Motor Phase U Current High. A fault in the automatic transmission control. Short, gentle driving to a shop is usually possible. Typical causes: low or degraded transmission fluid, failed shift or pressure control solenoid, faulty transmission speed sensor.
P0B03 — Auxiliary Transmission Fluid Pump Motor Phase V Current (P0B03): a powertrain (engine/transmission) fault affecting the automatic transmission control. Short, gentle driving to a shop is usually possible. Most often caused by internal mechanical wear (clutches, torque converter), low or degraded transmission fluid, valve body wear.
P0B04 — P0B04 — Auxiliary Transmission Fluid Pump Motor Phase V Current Low. 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, failed shift or pressure control solenoid.
P0B05 — P0B05 — Auxiliary Transmission Fluid Pump Motor Phase V Current High. A fault in the automatic transmission control. Short, gentle driving to a shop is usually possible. Typical causes: faulty transmission speed sensor, failed shift or pressure control solenoid, valve body wear.
P0B06 — P0B06 — Auxiliary Transmission Fluid Pump Motor Phase W Current. A fault in the automatic transmission control. Short, gentle driving to a shop is usually possible. Typical causes: failed shift or pressure control solenoid, internal mechanical wear (clutches, torque converter), low or degraded transmission fluid.
P0B07 — P0B07 — Auxiliary Transmission Fluid Pump Motor Phase W Current Low. 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, faulty transmission speed sensor.
P0B08 — OBD2 code P0B08 flags a problem with the automatic transmission control (auxiliary transmission fluid pump motor phase w current high). Short, gentle driving to a shop is usually possible. Common culprits: failed shift or pressure control solenoid, valve body wear, low or degraded transmission fluid.
P0B09 — Auxiliary Transmission Fluid Pump Motor Supply Voltage Circuit/Open (P0B09): a powertrain (engine/transmission) fault affecting the automatic transmission control. Short, gentle driving to a shop is usually possible. Most often caused by wiring or connector faults in the valve body harness, faulty transmission speed sensor, valve body wear.
P0B0A — P0B0A — Auxiliary Transmission Fluid Pump Motor Supply Voltage Circuit Low. 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), low or degraded transmission fluid.
P0B0B — P0B0B — Auxiliary Transmission Fluid Pump Motor Supply Voltage Circuit High. A fault in the automatic transmission control. Short, gentle driving to a shop is usually possible. Typical causes: wiring or connector faults in the valve body harness, faulty transmission speed sensor, failed shift or pressure control solenoid.
P0B0C — P0B0C — Auxiliary Transmission Fluid Pump Hydraulic Leakage. A fault in the automatic transmission control. Short, gentle driving to a shop is usually possible. Typical causes: internal mechanical wear (clutches, torque converter), wiring or connector faults in the valve body harness, failed shift or pressure control solenoid.
P0B0D — Auxiliary Transmission Fluid Pump Motor Control Module (P0B0D): a powertrain (engine/transmission) fault affecting the automatic transmission control. Short, gentle driving to a shop is usually possible. Most often caused by internal mechanical wear (clutches, torque converter), wiring or connector faults in the valve body harness, faulty transmission speed sensor.
P0B0E — Hybrid Battery Pack Current Sensor "B" Circuit (P0B0E): 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 control module driver fault, open or shorted wiring in the circuit, faulty sensor or actuator of the affected circuit.
P0B0F — OBD2 code P0B0F flags a problem with the sensor and actuator circuits (hybrid battery pack current sensor "B" circuit range/performance). The car is usually drivable while you plan the repair. Common culprits: blown fuse feeding the circuit, open or shorted wiring in the circuit, control module driver fault.
P0B10 — OBD2 code P0B10 flags a problem with the sensor and actuator circuits (hybrid battery pack current sensor "B" circuit low). The car is usually drivable while you plan the repair. Common culprits: open or shorted wiring in the circuit, poor ground connection, control module driver fault.
P0B11 — OBD2 code P0B11 flags a problem with the sensor and actuator circuits (hybrid battery pack current sensor "B" circuit high). The car is usually drivable while you plan the repair. Common culprits: poor ground connection, control module driver fault, faulty sensor or actuator of the affected circuit.
P0B12 — P0B12 — Hybrid Battery Pack Current Sensor "B" Circuit Intermittent/Erratic. A fault in the sensor and actuator circuits. The car is usually drivable while you plan the repair. Typical causes: faulty sensor or actuator of the affected circuit, open or shorted wiring in the circuit, corroded, loose or damaged connector.