The electronic control unit has a built-in self-diagnosis system, which continuously monitors the condition of the engine based on sensor signals. In the event of a malfunction, this system identifies it and informs the driver about it with a signal that is displayed by the indicator "CHECK ENGINE" ("check engine") he is "MALFUNCTION INDICATOR LAMP", located on the instrument cluster.
The diagnostic code can be determined using a scanner, or by the number of blinks of the indicator "CHECK ENGINE" with closed outputs "T" And "E" ("5" And "13" for production models from 5.2000 or "11" And "13" for production models up to 5.2000) diagnostic connector DLC (however, not all codes are displayed on the dashboard). If there are two or more faults, their indication starts with the smallest code (having the smallest number) and then continues in ascending order.