Hyundai 39160-37120 Relay Assembly-Power

Some of the electrical accessories of the vehicle include the fuel injection system, starter, and fog lamps; however, the relays work in directing electrical signals to the relative parts. Usually Relays work on Low current control circuit to switch on/off High current power circuit; if the Relay is faulty the concerned component will not work. The majority of car relays are placed inside the engine compartment fuse/relay box; however, several extraordinary relays are stored in the under-hood box at the fender. If a faulty relay is thought to be current, it can be analyzed out of its circuit or eliminated and transported to a dealer service department or repair shop for respective test. Entire defective relays must be replaced and the circuit controlled by relay usually has its identity marked on top of it and further identification can be found inside cover part of the relay box. Typical relays are classified into four types that include the normally open, the normally closed and other models that have the both. Usually terminals 1 and 2 are the control circuit to the relay and terminal 3 connects with the coil, while the other terminals make the power circuit. Depending on the relay's type, there may be graduated notches or other features on the case that help differentiate between the control and power circuit terminals. When testing a relay an ohmmeter should be connected across the terminals of the power circuit, continuity should not be obtained. For a usual four-terminal normally open relay, continuity should be obtained when the relay is on and should be absent when the relay is off. Jumper wire of this kind should be join one control circuit terminal to the positive battery terminal using another jumper wire the other end of the control circuit terminal to the ground; the relay should click, as the meter shows continuity. If the relay does not click, then you might have to change the jumper wires as polarity is a concern in these circuits. Where there is doubt concerning the relay's effectiveness, it should be replaced to avoid failure in the next test.

There are four basic types of relays: some are normally open, some are normally closed, and others include a circuit of each type.