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Fuses and relays
A WARNING Characteristics of fuses and circuits are subject to change due to the improvement of the design of the car. |
Fuses are used to protect electrical circuits against overload and short circuits. If an existing electric circuit connecting additional power consumers or because of a short circuit fault (which is nothing else but an excessive increase in current), the electrical circuit is overloaded. Wire winding and the generator are heated, the electrolyte in the battery may boil. To avoid this, to protect the electrical circuit fuses are used. If the current exceeds a certain allowable value, fuses interrupt the flow of current. To the car in case of failure are not left entirely without electricity, fuses are assigned to various electrical circuits. The fuse is determined by the presence of the wire conductor connecting contacts of the fuse. Always replace the fuse by another of the same value. Each contains the value of the protected fuse current. Never replace a fuse more than once, do not determine the cause of burnout. If the fuse is blown, it means that the conductor connecting contacts fuse is broken.
Fuse Ohmmeter check the integrity of the fuse. If the fuse burns out, the short-circuit or other fault. Find the cause and correct it before replacing the fuse.
A WARNING If the current flows in a circuit that exceeds the limit, the fuse will burn for 15 seconds. |
Circuit breakers The fuse may burn for two reasons. The cause responsible for the fuse to blow, can be easily identified visually after removing the fuse. The fuse has blown due to the high current overload. Before replacing the fuse with a new chain, check for a short circuit and components for damage. Only after eliminating the short circuit or replace damaged components can be installed fuse of the same rating. The fuse has blown due to repeated frequent on-off current user. Usually, this error occurs as a result of prolonged use or appears before burnout due to high current overload. In this case, you can simply replace the fuses with new ones designed for the same current.
A WARNING Fuse flat contacts identified by limiting current. If the fuse burns out, the new fuse should be the same amperage. If you use a fuse designed for high current, can be damaged by current users, and there is a danger of fire. To remove or install a fuse, use a special device, available in the fuse box. |
Relay Relay - is an electronically-controlled switch, which is normally used as follows: - The relay can switch large currents remotely from the circuit in which the current flows, allowing the use of thinner wires and contacts of switches; - At the relay may be more than one control input, unlike a mechanical switch; - Relays can function as a timer, for example, set the wiper interval. If the electrical circuit controlled by a relay fails, and the cause of the fault may be the relay, listen to the relay when the system. If the relay is working correctly, you hear a click when it is turned on. If the relay is serviceable, the cause of the fault in the elements, or connecting wires. If the relay does not work, then it does not get the main power or control pulse, or it is faulty. Most of the relay is set in the fuse and relay box in the engine compartment. Relay test For vehicles used four types of relays: the ever closed or open contacts and changeover contacts. In some cases the relay circuit diagram shows the relay contacts with numbers. To connect an ohmmeter to check the output relay contacts - it should show an open circuit. Then one additional wire connect contact relay coil to "weight", and the second an additional wire to connect the second contact of the relay coil to the positive terminal of the battery; relay should turn on (click), and the meter should show a short-circuit (resistance is zero). Otherwise, the relay is faulty and must be replaced.
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