Common faults and solutions for new energy vehicle DC charging

① Emergency stop fault is displayed on the screen

Possible cause: The emergency stop button of the charging pile was pressed manually.

Solution: Rotate and press the emergency stop button as prompted (usually the red/yellow button on the side)

② The charging gun cannot be pulled out: the gun is locked

Possible cause: the gun is pulled out directly without stopping charging; the gun head is locked due to operation error.

Solution: Manually unlock according to the gun head unlocking method.

③ The screen shows voltage (V) but no current or low current (A)

Possible cause: three-phase power is missing; power supply line wiring is loose.

Solution: Check whether the power supply line wiring is loose. If there is no problem with the line, contact the power supply department to check the overall line.

④ The screen displays no voltage (V) and no current (A)

Possible cause: DC contactor failure

Solution: Replace the DC contactor

⑤ The charging station suddenly turns off the screen

Possible cause: Check whether the line is loose or tripped. If not, it is generally a failure of the auxiliary power box

Solution: Replace the auxiliary power box

⑥Indicator light failure

Possible cause: AC power failure of the equipment

Solution: Check whether the circuit breaker inside the charging pile or the upper distribution box (cabinet) has tripped. If it is found to have tripped, please find out the cause and then close the circuit breaker. It is recommended to find an electrician to check.

⑦Dead screen phenomenon, no response when clicking the screen

Possible cause: system failure, system delay or freeze.

Solution: Press the emergency stop button, and then pop up the emergency stop button after about 5 seconds; if the display screen still has no response, open the front door, disconnect the air switch, and power off and restart. If it still cannot be solved, replace the screen.

⑧The air switch and leakage protector trip after power is turned on

Possible cause 1: Overload (when the load in the circuit exceeds the rated value of the air switch, the overload protection mechanism will be triggered, causing the air switch to trip);

Solution: Reduce the load, such as turning off some unnecessary electrical equipment, or replacing an air switch with a larger rated current;

Possible cause 2: Short circuit (when a short circuit occurs in the circuit, the current will increase sharply, causing the air switch to trip);

Solution: Check whether the wires and electrical equipment in the circuit are short-circuited. You can use tools such as a multimeter to detect and repair them;

Possible cause 3: Undervoltage (when the voltage is lower than the rated value of the air switch When the voltage is constant, the undervoltage protection mechanism may be triggered, causing the circuit breaker to trip);

Solution: Check whether the power supply voltage is stable. If the voltage is unstable, a voltage stabilizer may need to be installed;

Possible cause 4: Faults in the air switch or leakage protector itself;

Solution: Replace new air switches and leakage protectors to ensure the selection of reliable products;

Possible cause 5: Leakage (when leakage occurs in the circuit, that is, the current flows to the earth through an unexpected path, the leakage protector will detect this unbalanced current and trip);

Solution: Check whether the electrical equipment in the circuit has leakage, especially wires and equipment with damaged or aged insulation. Tools such as megohmmeters can be used to detect insulation resistance and repair leakage points;

Possible cause 6: Wiring error (when installing or repairing the circuit, if the wiring is incorrect, such as reverse or mixed connection of the N line and the PE line, the leakage protector may also trip);

Solution: Check whether the circuit wiring is correct and rewire according to the specifications;

Check one by one: First confirm whether there is a problem with the air switch and leakage protector itself, which can be tested by replacing new equipment. Then check the load, short circuit, leakage and other problems in the circuit one by one.

⑨The screen shows the handshake stage all the time-BMS communication failure

Possible cause 1: The BMS of the electric vehicle is abnormal.

Solution: Replace the vehicle and try again or re-plug the charging gun and try again.

Possible cause 2: The vehicle does not obtain the auxiliary power provided by the charging pile.

Solution: Check whether the charging connection cable is plugged in, whether the communication line is loose, whether the shielding line is grounded, and whether the auxiliary power connection is loose.

Possible cause 3: The charging connection cable is not connected in place or the communication line is loose.

Solution: Use a multimeter to check the continuity of S+ and S-.

Possible cause 4: The communication protocol of the charger and the electric vehicle does not match.

Solution: Capture the communication message and feedback the manufacturer to solve it on site.

Possible cause 5: The charging gun is damaged

Solution: Replace the charging gun

⑩ No response when plugging in the gun

Possible cause 1: The CC1 resistor of the gun head fails.

Solution: Use a multimeter to measure the resistance of the gun head at the gun head, determine the problem of the gun head, and replace the charging gun.

Possible cause 2: The CC1 detection of the main control board fails.

Solution: Replace the test method. If the CC1 of the main control board fails, replace the main control board.

No response when charging with a plug-in——Module offline

Possible cause 1: The 485 communication line between the DC energy meter and the control board is loose.

Solution: Use a multimeter to check whether the 485 communication line between the DC energy meter and the control board is abnormally connected, and check whether the communication indicator of the DC meter is flashing.

Possible cause 2: The CAN communication of the charging module is abnormal or the module cannot be output.

Solution: Use a multimeter to check whether the CAN communication line between the charging module and the control board is abnormally connected, open the right door to check whether the fault light of the charging module is on, or the charging module displays a fault code. If there is a fault, please contact the manufacturer in time or replace the charging module of the same model for testing and troubleshooting.