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.

15 codes
BMS_a167High

Onboard 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

CHG_f034Warning

DC 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_w012Low

Charge 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

DI_a023Critical

Inverter 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 Required

Tesla, Hyundai

P0A0CCritical

Main 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 Required

Tesla, Hyundai

P0A12Warning

EV 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 Required

Tesla, Hyundai

P0AA1Critical

High 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 Required

Ford, Hyundai, Chevrolet

P0AA4Critical

High 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 Required

Ford, Hyundai, Chevrolet

P0ADACritical

High 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 Required

Hyundai, Ford

P0D57Warning

EV 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

P0D59Medium

Charging 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

P177AMedium

Charge 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

P1A9096Critical

ICCU 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 Required

Hyundai, Ford

THC_a110High

Heat 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 Required

Tesla, Hyundai

THC_w044Warning

Battery 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