Oil Level Sensor For ECM: Description and Operation

GF18.40-P-4114AMG Component Description Of The Oil Level Check Switch







The oil level check switch is located at the right front in the oil pan top section.

The connector for the oil level check switch is located at the right front on the oil pan top section.







The oil level check switch is located at the rear front in the oil pan top section.

The connector for the oil level check switch is located at the rear front below the oil pan top section.

Task
The oil level check switch recognizes the minimum oil level in the engine oil pan and reports going below the minimum oil level to the ME-SFI [ME] control unit (N3/10).







Function
The engine oil from the engine oil pan reaches the oil level switch via 2 bore holes in the switch housing. The float is moved according to the oil level. The dry-reed contact is closed for an adequate engine oil level by the magnetic field from ring magnets. If the engine oil level becomes too low the dry-reed contact opens and the connection to the ground contact is interrupted. This recognized by the ME-SFI [ME] control unit and a suitable warning signal is sent via the CAN data bus to the instrument cluster (A1).

Short-term fluctuations in level are compensated for by to the size of the oil volume and the 2 bores in the switch housing
(e.g. during braking or for cornering) which avoids unnecessary warning signals.