The engine fault light is on, so it can run normally and the mechanic can't check the problem.

Generally speaking, there are two situations when the engine fault light is on:

The yellow symbol light (1) indicates that the engine is faulty, but the fault does not affect the normal operation of the engine, but it must be tested and repaired;

(2) The red symbol light indicates that the engine has a serious fault and needs to be repaired immediately under normal circumstances. If it is under special road conditions, you can drive in an emergency, but you need to pay attention to the working state of the engine at all times.

Matters needing attention

When the car is running or on fire, the car engine fault light on the dashboard lights up, usually red or yellow. Once lit, it will not disappear automatically in most cases and will disappear automatically in a few cases. This is the so-called engine fault light.

Engine fault signals are sent by ECU (engine computer), which controls all electronic devices of the whole engine, such as electronic throttle, fuel injector, generator and fuel pump. , covering intake, exhaust, fuel, ignition and timing systems. The reason why the engine fault light is on first, turn on the fault light, so as to tell the owner that there is a fault in the engine system at present and it is necessary to check and repair it in time.

Secondly, these fault information will be stored and provided to the mechanic for reference during maintenance, so as to solve the fault more quickly. Furthermore, in order to ensure that the engine can continue to operate in the event of a fault, if the detected fault has little effect on the engine operation, the computer will directly ignore it, but in fact, the engine is not in good working condition at this time.

If a serious fault is detected, the computer will start the emergency program, and the engine can work under the emergency program, but generally only to ensure that the engine can continue to run without stalling.

In this case, it is necessary to make a preliminary judgment: disconnect the positive or negative electrode of the automobile battery for a few seconds, and then install it. After that, start the car and see if the engine fault light of the instrument will still light up. If not, there is nothing wrong with the engine, so there is no need to go to the repair shop for inspection. Some high-end cars will lose a lot of data after power failure and need to be reset. After the power is cut off, you may encounter two situations:

1. The fault light went out just now, and it came back on a few days later.

2. After the power is cut off, the fault light still does not go out. In this case, the engine really broke down, so we have to go to the repair shop for testing.