With Up-Level Cluster

The oil pressure sender/switch, used on vehicles with the up-level cluster, is a dual function sender/switch that provides a variable resistance (0-240 ohms) to the oil pressure gauge and a normally closed contact set, that opens with oil pressure, for the oil pressure indicator lamp.

The normally closed contact set opens with oil pressure after the engine is started. The contacts closes when oil pressure drops below a specified limit. With the contact set closed, a ground is supplied for the oil pressure indicator lamp, allowing it to illuminate.