Engine control light
The engine control light , Malfunction Indicator Light (MIL), is part of the on-board diagnosis for motor vehicles, which was initially required in California and now also in other states and countries . It is a control lamp in the instrument cluster . Typically, the MIL is characterized by a stylized motor.
purpose
If the on-board diagnosis has detected an emissions- relevant, i.e. exhaust-gas- relevant fault, the driver is prompted to visit the workshop by lighting up or flashing of the control lamp in order not to unnecessarily endanger the vehicle or the environment.
| Mil | meaning |
|---|---|
| Brief flashing | A temporary error was detected. However, the error does not require any further attention because it is not permanent |
| Permanent glow | An error has occurred and should be fixed soon (in a workshop). There is no immediate danger to the vehicle or the environment |
| Flashing quickly | A fatal error has occurred. The vehicle should be repaired immediately to avoid consequential damage. Reduce speed and load (acceleration) significantly - it is best to switch off the engine. |
Legal requirements
When and for which faults the engine control lamp has to light up is stipulated in the legal regulations for on-board diagnostics. This also includes a function test: it must light up briefly when the engine is started. If that does not happen, a workshop visit is required. In states with particularly restrictive environmental legislation (such as California) it also happens that police officers check the engine control lamp during vehicle checks, since once it has lit, driving to the next workshop is only allowed.
Shutdown
In the event of sporadic errors (e.g. loose contact ), the engine control lamp may go out after the error has disappeared or after the next engine start. Otherwise, this can only be done by reading out and deleting the fault memory in the workshop.
literature
- Kurt-Jürgen Berger, Michael Braunheim, Eckhard Brennecke: Technology automotive engineering. 1st edition, Verlag Gehlen, Bad Homburg vor der Höhe, 2000, ISBN 3-441-92250-6
- Hans-Hermann Braess, Ulrich Seiffert: Vieweg manual automotive technology. 2nd edition, Friedrich Vieweg & Sohn Verlagsgesellschaft mbH, Braunschweig / Wiesbaden, 2001, ISBN 3-528-13114-4