Low Oil Pressure Warning Indicator

The SJB is hardwired to the oil pressure switch. The oil pressure switch consists of a diaphragm and contact points, which are normally open. When there is low or no oil pressure, the oil pressure switch remains open, removing the ground to the SJB. When sufficient oil pressure exists, the oil pressure switch closes, providing a ground signal to the SJB. The SJB monitors the oil pressure ground signal and sends a message to the instrument cluster to turn the indicator on or off according to the engine oil pressure.