Maintenance indicator (BMW 5 Series E12)

Some cars were equipped with a maintenance indicator. This indicator determines the frequency of maintenance depending not only on the mileage, but also on the operating and driving conditions (frequent short-distance trips, long-distance trips, "economical" driving style, etc.). The memory device (MD) of the indicator receives information about the car's mileage, crankshaft speed, operating time and engine coolant temperature.



The indicator is built into the instrument cluster and has an autonomous power supply from rechargeable batteries, ensuring that data is saved in the memory for four months after the battery is disconnected. The indicator is reset using an electronic key from BMW, connected to terminal "7" of the diagnostic socket. It consists of nine signaling devices (lEDs), five of which are green, one yellow and three red, as well as two light boards located above them: OIL SERVICE and INSPECTION.

Operating principle

After the car has driven the first 2000 km, after the indicator has returned to its initial state, the readings in the form of the indicator lights and display should be interpreted as follows.



When the ignition is turned on, a number of green indicators light up (maximum five), which go out after the engine is started. The number of illuminated indicators decreases as the vehicle is used, thus indicating that the time for maintenance is approaching.

After all the green indicators go out, the yellow indicator starts to light continuously at the same time as one of the displays (it does not go out even after starting the engine). This indicates the need to perform maintenance operations corresponding to the illuminated indicator light as soon as possible.

If the vehicle is operated continuously, the red indicators light up and do not go out at monthly intervals. Do not operate the vehicle with the red indicators lit.

Maintenance intervals

The indicator usually shows the maintenance intervals in the following order:

• when the OIL SERVICE indicator lights up, replace the oil in the engine crankcase and the filter element of the oil filter, and, if necessary, perform a vehicle safety check;
• when the INSPECTION indicator lights up for the first time, perform the maintenance operations provided for in the "Check I" program;
• if the OIL SERVICE indicator lights up again, repeat the operations indicated above;
• if the INSPECTION indicator lights up again, perform the maintenance operations provided for in the "Check II" program.

Subsequently, repeat the maintenance operations, alternating the "Check I" and "Check II" programs.

Note. On vehicles with low annual mileage, the INSPECTION indicator lights up annually. In this case, the "Check I" or "Check II" programs should be performed, observing their sequence. At the same time, perform the maintenance operations performed annually or every two years of vehicle operation.

Maintenance card