Toyota 90987-02027 Relay

A fuse disconnects a circuit when a certain amount of current flows through it and can be used for safeguard of components and wires and all other forms of wiring from high amounts of current, usually as a result of a fault ,more commonly a short circuit. The primary fuses are arranged in the fuse compartment that is accessed by a panel in the stowage tray in front of the driver's seat; additionally, there are secondary fuses in the second fuse compartment positioned in the engine compartment adjacent to the battery. To gain access to the fuses pull the fusebox lid from the rear of the storage tray forward or remove off the lid of the fuse box on the engine compartment. In case of a blown fuse you will see that the wire of the fuse is either melted or broken. When undertaking the removal of the fuses, it is necessary to turn off the corresponding circuit; preferably, the battery should also be disconnected. An additional action that could be taken if using the thin-nosed pliers is to remove the fuse from wherever it was finding its way. Use a correct fuse rating where a fuse has blown, and never replace it with the wrong or higher one or make temporary connections, as this can result to more severe damage or occasion a fire. The fuses are colour-coded, and have specific ratings noted on the casing while large 'midi' fuses located in the engine compartment fuse box are ideal indications of serious wiring problems if blown. Relays are used for a number of reasons such as change over heavy currents at a remote location, when a device is required to receive many control signals, relay with timers. The relays are in the under-facia fusebox and the engine compartment fusebox, although some models have a relay box additionally. When a circuit which is controlled by a relay gets a fault, switching should provide an audible tone of 'click' if the relay is operational; if the relay do not produce the tone then the relay may not be receiving power or simply a faulty relay. Functional testing can be done by substituting with a know to be good unit, however, care must be taken since some relays look alike but are differ in functionality. To take out a relay, the circuit has to be off, after that, one pulls it out from the slot and plugs it in as a normal practice would prescribe.

If a faulty relay is suspected, it can be removed and tested using a specific procedure or by a dealer service department or repair shop. Defective relays must be replaced as a unit.

Some electrical accessories in a vehicle that use relays include the fuel injection system, horns starter, and fog lamps.

If the relay fails the test, it should be replaced.

If the relay fails the test, it should be replaced.

If the relay doesn't click, try swapping the jumper wires on the control circuit terminals, as polarity may be critical.

On most relays, two terminals are for the relay control circuit (connecting to the relay coil), and the other terminals are for the power circuit (connected together within the relay when the control-circuit coil is energized).

Several electrical accessories in a vehicle that use relays include the fuel injection system, horns, starter, and fog lamps.

The main fuses are located in the fusebox, behind a panel in the driver's storage tray. Additional fuses are located in a second fusebox in the engine compartment, next to the battery.

If the relay is defective, the component it controls will not operate properly.