Pacific Automotive Network used a fault diagnostic instrument to check the vehicle, which showed a low voltage fault. Based on the previous fault phenomenon, the maintenance personnel determined that there are the possible causes of the fault: fault of the generator itself; battery sensor (IBS) fault and battery damage;
According to the maintenance principle from easy to difficult, the maintenance personnel first check whether the battery is aging and damaged. Use a battery tester to test the battery and find that it is in good condition, ruling out the possibility of a malfunction caused by battery damage.
The battery sensor (OBS) is a sensor that detects the power consumption of the vehicle body. It and the generator are components of the BSD subbus system. Unplug the IBS connector, put the BSD system into emergency mode, then bootez the vehicle to check the generator's power output. It turns out that it still does not generate power, so the generator itself is judged to be faulty. After replacing the generator and testing the car, the fault disappeared and the vehicle was delivered.
However, the user drove the vehicle to the store on the second day and reported an alarm on the dashboard, indicating that the battery voltage was too high. I used a troubleshooting tool to check the vehicle and found a BSD generator fault prompt. I checked the generator's power output and found that it was indeed too high. Could it be that the new generator is defective? This possibility is extremely low. In order to check the quality of the generator, we found a known good model of the same model and performed a swap test on the generator. Once the exchange is complete, the vehicledefective still had problems, while the normal vehicle had no abnormalities, indicating that there was no problem with the generator.
Just when the maintenance staff was confused, they suddenly found an old set of ignition coils in the luggage compartment of the car. After asking the user, I learned that the car's ignition coil was just replaced some time ago and the problem occurred shortly after the replacement. Could it be that the ignition coil is defective? Before the inspection, the maintenance personnel first understood the component composition principle of the ignition coil. Current passes through the primary winding to generate a magnetic field, and the generator regulator is made up of several diodes if the magnetic field ignites. the coil interferes with the regulation of the generator. The secondary tube inside the Dregulator will cause the regulator to malfunction.
After understanding the working principle, the maintenance personnel checked the vehicle's ignition coil and found that it was not an original part, so they suspected that the fault was in the ignition coil.
Troubleshooting: After replacing the original ignition coil, take a test drive, the fault disappears, use the diagnostic tool to check the vehicle fault code, no fault code error exists, the fault is eliminated.
(Images/Text/Photos: Pacific Automotive Network Calling the Beast Q&A)