The service interval display (SIA ) serves the driver and the workshop as an indication showing that an engine oil service, distance inspection or time inspection is due. The inspection intervals of the vehicle are not rigidly referred to the kilometres covered but rather they depend on the consumption. The current service interval status is displayed as of "Terminal 15 ON" for 10 seconds after reaching a minimum engine speed of 400 rpm.
The data of the service interval display (SIA ) are also stored in the light check module (LCM ).