Fault Code Database
EV DTC Code Library
Browse diagnostic trouble codes for every major EV platform. Click any code to start the step-by-step repair wizard.
B1023LowBody Control Actuator Hardware Fault
The central body control module has detected an electrical open or short circuit inside one of its physical electronic actuator loops. This typically stops minor comfort systems from functioning, such as automated vent flaps, electronic glovebox latches, or steering column adjusters.
Tesla
B1234LowBody Controller Unexpected Wake State
The vehicle's primary body control network is failing to sleep when parked, staying stuck in an active state that draws continuous current. This internal logic bug prevents the vehicle from entering deep sleep mode, rapidly draining the low-voltage 12V auxiliary battery overnight.
Tesla, Rivian, Ford
BMS_a035CriticalBMS Critical Structural Fault Detected
The high-voltage Battery Management System has identified a structural hardware fault or internal component fracture inside the under-car battery containment envelope. This is a severe safety code indicating internal physical damage, structural degradation, or a catastrophic failure within the structural pack assembly.
Shop RequiredFord, Chevrolet
BMS_a063HighTesla Charge Port Power Conversion Failure
The Battery Management System has lost its high-voltage connection to the vehicle's onboard Power Conversion System (PCS). This safety-critical hardware error prevents the vehicle from accepting any AC home charging or managing DC fast-charging sessions safely.
Tesla
BMS_a066HighDegraded High Voltage Battery Modules
The high-voltage pack management module has mapped severe, irreversible capacity loss across specific internal battery cells. This means the affected cells are unable to safely accept standard current loads, heavily truncating full driving range and forcing the car into a permanent state of reduced performance.
Shop RequiredNissan, Tesla
BMS_a167HighOnboard Charging System Hardware Fault
The Battery Management System cannot establish proper current control loops with the integrated internal AC onboard charger module. This prevents the vehicle from taking in standard alternating current from home wall boxes or public level 2 charging units.
Tesla, Kia, Hyundai
BMS_u029HighInternal Battery Pack Monitor Communication Loss
The Battery Management System dropped its data connection with an internal cell-monitoring circuit card inside the HV battery casing. Without real-time cell temperature and voltage data, the car caps charging and range to protect the pack from thermal runaway.
Tesla
BMS_u050CriticalRapid Cell Impedance Imbalance Detected
The Battery Management System has flagged a dangerous, rapid spike in internal electrical resistance across an isolated group of battery cells. This severe cell delta limits regular acceleration power and blocks normal charging currents to eliminate thermal runaway risks.
Shop RequiredTesla
BRK_a024WarningRegenerative Braking Control Fault Active
The vehicle's braking controller has logged an electrical fault that restricts or completely turns off regenerative braking. Because kinetic energy can no longer be converted back into battery charge, the vehicle relies solely on its mechanical friction brakes, altering brake pedal feel.
Tesla, Nissan, Chevrolet
C1210WarningBrake Fluid Level Sensor Fault
The electronic brake controller has picked up an erratic or out-of-spec voltage signal from the fluid level switch on the brake master cylinder reservoir. This triggers immediate safety warnings on your dashboard because the car cannot verify if it has adequate brake fluid pressure.
Shop RequiredTesla, Nissan, Toyota
C123CWarningRegenerative Braking Circuit Performance Error
The electronic stability and braking network has detected an electrical discrepancy inside the isolation valve circuit assigned to regenerative deceleration blending. This breaks coordination between electronic motor braking and hydraulic friction stop loops.
Tesla, Nissan
C1241MediumLow Auxiliary 12V System Operating Voltage
The auxiliary 12V battery powering the car's computers, door locks, screens, and safety relays has dropped below safe voltage. Even with a full traction battery, a dead 12V leaves the car unable to start or triggers a flood of false error codes across the dashboard.
CHG_f034WarningDC Fast Charging Performance Degraded
The vehicle has restricted DC fast-charging speeds due to an identified issue inside the fast-charging safety control line. While you can safely charge at standard rates using your home AC wall box, fast charging at public stations will run at deeply throttled speeds.
Tesla, Hyundai
CHG_w012LowCharge Port Latch Engagement Warning
The charge port controller is warning that the internal locking latch failed to clamp securely around the charging handle pin. Because high-voltage charging cannot safely begin without a locked handle, the vehicle will block power flow until a lock is achieved.
Tesla, Ford, Hyundai
CP_a051LowCharge Port Door Sensor Communication Loss
The charge port control unit lost its digital connection with the push-to-open inductive sensor in the door flap. The push-to-open shortcut is disabled but the charge door still works via touchscreen, app, or charging cable button.
Tesla
DI_a023CriticalInverter Gate Driver Circuit Fault
The drive inverter's internal logic card has tracked a critical hardware failure inside the transistor gate driver network. This component converts the high-voltage battery's DC power into the AC waveforms that spin your drive motors, meaning a fault here causes complete propulsion loss.
Shop RequiredTesla, Hyundai
DI_a040HighDrive Unit Phase Current Fault
The motor control module has detected an irregular electrical wave mismatch across the three individual power phase cables running into the drive motor. This severe electrical deviation causes immediate limp-home modes or shuts down the drive unit to protect circuits from high-amp shorting.
Shop RequiredTesla, Ford
DI_a134HighDrive Inverter Fault Turtle Mode Active
A severe software or internal thermal fault inside the drive inverter assembly has forced the car into emergency Turtle Mode. Maximum driving speed and motor acceleration are heavily limited to protect the drive system from permanent electrical breakdown.
Shop RequiredTesla, Nissan
DI_w014WarningDrive Unit Mechanical Bearing Warning
The drive unit housing sensors have logged an anomalous structural signature or high thermal spike coming from the main internal rotor shaft bearing. This indicates internal mechanical wear that, if ignored, can damage the motor's core gear teeth.
Shop RequiredTesla, Ford
MCU_w023LowMedia Control Unit Warning Active
The car's primary infotainment and Media Control Unit has logged a non-fatal internal logic glitch or high processor temperature loop. While the vehicle remains fully safe to drive, secondary convenience features like GPS tracking, sound systems, and camera feeds may lag or freeze.
Tesla, Ford
MCU_z001HighInfotainment MCU Screen Component Failure
The primary central dashboard touchscreen assembly has suffered an electrical component failure, causing a permanently blank screen, flashing backlights, or non-responsive touch inputs. Because vital climate settings and speedometer data can be tied to this screen, a failure here requires quick repair.
Tesla
MECH_BEAR_001CriticalWheel Bearing Assembly Failure Roaring
One of the vehicle's mechanical wheel hub bearings has suffered internal metallic breakdown along its ball races. This generates a distinct low-pitched roaring hum or grinding noise that grows progressively louder as you accelerate up to highway speeds.
Shop RequiredMECH_BRAKE_001LowBrake Pad Surface Rust Squeak
Because electric vehicles use high amounts of regenerative braking, the physical iron brake rotors are rarely clamped hard by the brake pads. This causes a thin layer of surface rust to accumulate on the discs, creating a loud squeaking sound during initial morning stops.
MECH_DOOR_001LowFlush Door Handle Failure To Actuate
The vehicle's aerodynamic flush-mount motorized exterior door handle assembly has encountered a mechanical breakdown or a broken link wire inside the door skin. The handle stays retracted inside the door body, blocking physical entry to the car.
Tesla
MECH_HEAT_001WarningCabin Heating Climate Control Failure
The climate control system is completely unable to heat the vehicle's interior cabin space due to a component failure in either the high-voltage PTC heater matrix or the electronic heat pump assembly. The vents will blow cold air despite turning up dashboard heat settings.
Shop RequiredMECH_MCU_001WarningCentral Touchscreen Blank Screen Freeze
The vehicle's central control screen has suddenly frozen or turned completely black due to an internal computer lockup or low-voltage power rail drop. Because this single screen handles everything from mirror adjustments to speed readouts, a lockup can disable convenience features.
MECH_PWR_001CriticalSudden Complete High Voltage Power Loss
The vehicle has experienced an instantaneous complete loss of high-voltage drivetrain propulsion while actively driving on the road. This dangerous fault is typically triggered by a sudden opening of the primary high-voltage battery safety contactor relays to isolate a major circuit issue.
Shop RequiredMECH_S3Y_001WarningFront Suspension Squeak Control Arm Bushing
A highly prominent mechanical squeaking or creaking noise is heard from the front suspension when steering or driving over bumps. This is a common mechanical issue caused by water ingress washing out the grease inside the front upper control arm ball joints and rubber bushings.
Shop RequiredTesla
MECH_TIRE_001WarningHighway Speed Acoustic Foam Tire Vibration
The vehicle exhibits a distinct aggressive steering wheel shaking or interior cabin vibration specifically at highway speeds. This is often caused by the specialized internal acoustic noise-dampening foam layer inside the EV tire peeling away from the tread interior and bunching up into a balance-destroying lump.
Shop RequiredMS_a012LowDoor Handle Actuator Assembly Fault
The driver or passenger side automated door handle mechanism fails to present or extend outwards when the car unlatches. The internal motorized microswitches or cast paddle gears have cracked under cyclic fatigue stress, locking users out of the vehicle cabin.
Tesla
P0A0CCriticalMain High Voltage Battery Critical Fault
The vehicle's central interlock control system has logged an unacceptably low voltage or circuit break along the high-voltage safety loop line. This severe fault code acts as a master safety trigger, locking open the battery pack contactors and disabling the powertrain to avoid electrocution risks.
Shop RequiredTesla, Hyundai
P0A12WarningEV Battery Cooling Fan Performance Fault
The vehicle control computer has detected an open circuit, low voltage draw, or complete hardware failure within the auxiliary electric fan network tasked with cooling the main battery pack array. Without this fan pushing air, battery cell temperatures can quickly climb during rapid charging sessions.
Shop RequiredTesla, Hyundai
P0A7FHighHigh Voltage Battery Pack Severe Deterioration
The powertrain control module has determined that the high-voltage lithium traction battery pack has degraded past an acceptable engineering limit. The battery's internal chemical cells can no longer sustain proper high-current output, heavily capping available vehicle acceleration and total driving range.
Shop RequiredNissan, Tesla, Fiat
P0A80HighHybrid Battery Pack Degradation Detected
The hybrid powertrain control module identified an unacceptable voltage variance between cell modules inside the main traction pack. This points to a weak or failing battery group that can no longer hold its designated charge.
Toyota, Lexus
P0AA1CriticalHigh Voltage Battery Welded Positive Contactor
The Battery Management System has identified a dangerous hardware fault where the primary positive high-voltage contactor relay switch has physically welded itself shut due to an electrical arc. This means the lethal high-voltage energy grid stays live outside the battery case even when the vehicle is completely shut off.
Shop RequiredFord, Hyundai, Chevrolet
P0AA4CriticalHigh Voltage Contactor Switch Logic Error
The vehicle's main powertrain monitor has logged an incorrect operation sequence across the primary high-voltage battery contactor switches. The vehicle cannot confirm if the internal high-current relays are correctly open or closed, triggering an immediate non-start condition to protect modules.
Shop RequiredFord, Hyundai, Chevrolet
P0ADACriticalHigh Voltage Junction Box Structural Failure
The internal power distribution junction hardware located inside the main battery container has suffered an electrical component failure or insulation breakdown. This prevents safe high-voltage routing between the core battery modules, the drive motors, and the onboard charger.
Shop RequiredHyundai, Ford
P0C11HighDrive Motor Inverter Phase Circuit Short
The main powertrain computer has detected a serious short circuit or abnormal high-current drop inside the internal phase drive circuits of the electric motor inverter module. This stops the car from safely spinning the drive motor, causing an immediate halt in power delivery.
Shop RequiredFord, Jaguar
P0C2FWarningEV Thermal Management System Control Error
The primary vehicle control computer has lost operation over the intricate network of electronic multi-way directional valves that route cooling fluid through the battery pack and powertrain. This leaves the car unable to cool its battery cells or warm its cabin, throwing the car into limp mode.
Shop RequiredTesla, Ford
P0C73MediumMotor Electronics Coolant Pump Performance Failure
The auxiliary electric coolant pump cooling the drive motors and power inverter is spinning at an incorrect speed or drawing improper current. This leaves electronics prone to overheating under heavy loads, triggering immediate power derating (limp mode).
Rivian
P0D22WarningEV Charging Current Sensor Circuit Fault
The onboard charging control module has logged an erratic or completely absent voltage signal from the high-voltage direct-current charging sensor. Because the vehicle cannot accurately track how many amps are pouring into the battery pack, it halts charging to prevent overcharging cells.
Nissan, Tesla
P0D57WarningEV Charging Circuit Low Input Error
The vehicle's high-voltage charging management computer has identified an unexpected low-voltage signal drop on the charging handle command pilot communication line. This communication breakdown prevents the car from safely negotiating power delivery with home or public charging stations.
Kia, Hyundai
P0D59MediumCharging Proximity Circuit Voltage High Input
The charging control system detected an out-of-bounds voltage on the charge port plug proximity detection line. This breaks the safety loop that verifies the charging gun is fully locked in, locking out charging to prevent arc damage.
Hyundai, Kia
P177AMediumCharge Port Actuator Motor Jammed
The automated charge port door locking actuator pin mechanism has encountered a mechanical jam or internal motor electrical failure. The car cannot physically slide the metal security locking pin into the charging handle latch hook, preventing any high-power charging sessions from initiating.
Tesla, Hyundai
P1A10HighFord High Voltage System Emergency Shutdown
The primary control module triggered an emergency isolation of the high-voltage electrical network to minimize arc risks. This hard fault typically stems from a breakdown or bad safety contactors inside the main battery distribution hardware.
Ford
P1A4BWarningPowertrain Performance Control Logic Error
The central drive control processor has identified an internal processing computation variance across its motor acceleration tracking arrays. This discrepancy causes the vehicle to drop torque delivery and slip into a safe default power state to prevent unintended acceleration.
Shop RequiredTesla
P1A9096CriticalICCU DC/DC Converter Hardware Fault
The vehicle's Integrated Charging Control Unit (ICCU) has suffered an internal hardware sensor failure within its built-in DC-to-DC converter matrix. This critical failure blocks the car's ability to pull high-voltage battery power down to maintain the auxiliary 12V loop, causing the car to quickly lose electronic systems.
Shop RequiredHyundai, Ford
P1B0EHighElectric Drive Inverter Transistor Module Fault
The high-voltage drive inverter detected an internal hardware breakdown tracking improper power waves across its switching transistors. This represents physical circuit degradation inside the gate driver assembly, causing sudden loss of drive propulsion.
Lucid
THC_a102CriticalBattery Thermal Excursion Safety Limit Reached
The thermal control framework has tracked extreme, dangerous peak temperature numbers within the main high-voltage battery array blocks. The car will lock open safety contactor blocks and stop all driving or high-power fast charging loops to eliminate battery fires.
Shop RequiredNissan, Tesla, Ford
THC_a110HighHeat Pump Refrigerant System Failure
The advanced central climate heat pump system has entered a protective lock state due to an internal hardware breakdown, a failed electronic expansion valve, or low structural refrigerant pressure. The car cannot warm or cool its battery pack or passenger cabin spaces efficiently.
Shop RequiredTesla, Hyundai
THC_w021WarningAC Compressor Low Efficiency Warning
The vehicle's high-voltage electric air conditioning compressor is underperforming, failing to create appropriate refrigerant pressure levels while running at full rotational speeds. This warning flags a failing compressor pump component before it completely breaks down and clogs the cooling loops with metal dust.
Shop RequiredTesla, Nissan, Volkswagen
THC_w044WarningBattery Cooling Loop Low Performance
The vehicle's central thermal management module has identified insufficient heat dissipation across the main high-voltage battery cooling loop. The battery will struggle to shed heat during fast-charging sessions or sustained highway driving, leading to throttled charging speeds.
Tesla, Hyundai, Volkswagen
U0100HighDrive Motor Control Module Lost Communication
The main network hub lost all communication with the drive motor inverter across the CAN bus line. Without vital speed and power management data, the vehicle enters a disabled or non-operational state.
GM
U0140HighLost Communication With Body Control Module
The vehicle's high-speed central data network has lost all real-time data connection contact with the primary Body Control Module (BCM). Because this computer module controls basic infrastructure like exterior lighting, door electronic latches, and window systems, a communication drop bricks peripheral operations.
Ford, Polestar
U1000LowOver-The-Air Update System Internal Fault
The vehicle's main network gateway has logged a deep internal processing error or firmware file corruption during an attempted Over-The-Air (OTA) software update. This system hang-up can lock or disable specific vehicle modules, preventing the car from clearing old fault memories until the software is restored.
Tesla, Ford, Rivian
VCFRONT_a182HighLow Voltage Auxiliary Battery Replacement Required
The front vehicle controller has tracked severe capacity loss or a failing internal cell within the low-voltage auxiliary accessory battery. This battery runs the vehicle's secondary computers, lighting, and safety relays, meaning an unaddressed failure here can leave the car unable to unlock or power up.
Tesla