What does it mean that a yellow icon similar to an alarm clock is displayed on the instrument of Volkswagen?

It is an engine fault light; Generally, this light will turn on the self-test after the vehicle is powered on, and will go out when the vehicle is actually started. But it will also light up because of problems with the vehicle. Although this light is often referred to as an engine failure light, it is actually an exhaust emission warning light. Under normal circumstances, this light will not go out, which means that the vehicle exhaust emissions may exceed the standard and need to be overhauled.

The unqualified exhaust emission is mostly due to carbon deposition. If the warning light is on for this reason, carbon deposition is often very serious. Regular refueling at ordinary times, minimizing idle time and using the first-class fuel treasure regularly are all effective means to slow down the formation of carbon deposits. Their main function and purpose is to help gasoline burn fully and reduce residue.

Engine fault light reminds us that it is not only the cause of exhaust emission, but also the problem of sensors or other mechanical parts, which leads to the failure or deviation of exhaust emission monitoring. At this time, the warning light will also light up, so the owner can't find out that the engine fault lights up or go to the repair shop to check the real reason and really solve the vehicle problem.

Extended data:

The reason why the engine fault light is on:

Ignition coil is damaged: the ignition coil is located at the upper part of the spark plug, and its function is to provide high-voltage pulse current to the spark plug according to the instruction of the engine computer, so that the spark plug can generate sparks for in-cylinder ignition. The direct effect of the damage of ignition coil is that the spark plug can't ignite, which leads to the engine cylinder failure.

Thermostat damage: Thermostat is a small device between engine and radiator, which can open or close the passage of coolant to radiator according to engine temperature. The function of thermostat is to keep the engine working at the optimum temperature. If the thermostat breaks down, the temperature of the engine will be out of control.

Nozzle damage: Nozzle is a device that injects fuel into the engine. It ejects atomized fuel and then mixes it with air to form an oil-gas mixture for the engine to burn. If the fuel nozzle is damaged, it will affect the fuel injection quantity, resulting in the loss of engine cylinder or power reduction.