Component description of the oil level check switch - GF18.40-P-4114P

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ENGINE 642 in MODEL 164.1 /8, 203.0 /2, 209.3 /4, 211.0 /2 /6, 219.3, 221.0 /1, 251.0 /1

ENGINE 642 in MODEL 463

Fig 1: Identifying Oil Level Check Switch

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Location

The oil level check switch is located on the underside of the engine and is fastened with the base plate on the inside on the large oil pan. The jack for the oil level check switch is located on the output side at the lower left.

Task

The oil level check switch has the task to record the oil level and forward this over a discrete line to the CDI control unit (N3/9).

Body

Shown on engine oil level greater than "Min"

Fig 2: Identifying Oil Level Check Switch Components

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Function

The engine oil levels in the oil level check switch and oil pan balance out over the feed and drain bore. The float is moved according to the oil level. The dry-reed contact is opened off for an engine oil level less than "Min" and closed for an engine oil level greater than "Min" by the magnetic field of the ring magnets. If the dry-reed contact is opened then the connection to ground contact is interrupted and a warning message appears in the multifunction display (A1p13) in the Instrument cluster (A1) concerning an unacceptably low oil level.

The volume of the housing and size of the drain bore on the oil level check switch compensate for short-term level fluctuations and thus unnecessary warning messages. Level fluctuations can occur, for example, during cornering.