Fault Description: 

2017 JAC iEV6E pure electric vehicle, with a total mileage of about 150,000 kilometers. The owner reported that the charging connection indicator light does not turn on during charging, there is no charging current indication, the power battery cannot be charged, the vehicle speed is below 30 km/h, and other systems are working normally.

Troubleshooting process:

First, measure the voltage of the small battery, which is 13.8V, normal; measure the working voltage output of the charging station and the charging gun, about AC220V, also normal; measure the resistance between the CC terminal (Charge Connect Confirmation terminal) and the PE terminal (Protective Earth terminal) of the charging gun, about 1.5kΩ, also normal;

Next, measure the voltage between the CP (Charging Power Confirmation terminal) of the charging gun and the PE terminal, which is about 12 V, no problem.

At this point, the possibility of a fault in the charging gun or charging circuit can basically be ruled out. The appearance of the slow charging port was checked, and no rust or damage was found; then the resistance between the CP and PE terminals of the vehicle's slow charging port was measured, approximately 87.3 kΩ (normally should be greater than 50 kΩ), which is fine;

Next, the voltage between the vehicle's slow-charging CC terminal and the PE terminal was measured, which was about 12 V (normally it should be around 6 V), indicating the voltage is too low. At this point, it was basically suspected that there was a short circuit between the vehicle's slow-charging interface terminals CC and CP. Using a multimeter in buzzer mode to measure, it was found that the vehicle's slow-charging interface terminals CC and CP were conductive. By carefully inspecting the low-voltage signal harness between the vehicle's slow-charging interface and the onboard charger, it was finally found that a copper wire inside the connector of the onboard charger's low-voltage signal cable shorted terminal 3 (CP terminal) and terminal 4 (CC terminal) together. It was inferred that the fault was caused by this.

Troubleshooting: After cleaning the copper strands inside the low-voltage signal wire connector of the charger, test the vehicle. The vehicle's charging returned to normal, and the fault was cleared.