What happened when the trouble light of Nissan Qi Jun engine came on?

About the landlord's concern, "What happened when the Nissan Qi Jun engine fault light came on?" The following is my personal opinion:

The reasons for the failure light of Nissan Qi Jun engine are as follows:

1, the exhaust emission is not up to standard, such as poor fuel, failure of three-way catalyst, excessive carbon deposition in intake pipe, blocked fuel nozzle, failure of oxygen sensor, occasional misfire of engine, etc. , engine fault lights will be on, and poor oil quality will lead to the most engine fault lights;

2. The fault light is on due to poor engine system, such as the fault of accelerator pedal sensor, throttle position sensor, air flow meter and crankshaft position sensor. Or poor line contact, etc. , it will cause the engine fault light to light up;

3. Some vehicle gearbox system failures are also indicated by engine failure lights, such as internal gearbox failures, slippage, high temperature, etc.