1. The wrong ignition coil is used. The appearance of the ignition coil of the engine of some models is the same, but there are modules installed inside the coil and the modules are not arranged. For example, BYD's new F3 has two different engines with different ignition coils, one with a built-in module and one without a module, but the appearance of the ignition coil is the same. The ignition coil appearance of Cruze 1.6 and Cruze 1.6T is almost the same. But the Cruze 1.6 coil is not equipped with modules; the Cruze 1.6T coil is equipped with modules.
2. The wiring harness plug on the car engine is in loose contact with the ignition coil socket, and there is no contact. The external current does not pass through the ignition coil's low-voltage socket, and the ignition coil does not work at all.
3. The built-in module of the ignition coil fails and is damaged after working, and the ignition coil cannot work.
4. The low-voltage part of the ignition coil is soldered. Desoldering due to failure or long-term vibration of the coil, the ignition coil is damaged and cannot continue to work.