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Electrical circuits
| PERFORMANCE ORDER | | 1. The usual electric chain consists of elements of the electric equipment, switches, relays, motors, fuses, fuse links and connectors and cables that connect all the elements together, the battery and the "weight" of the car. | | 2. The cause of the fault can be found much faster, if it is determined which of the elements of this chain work normally. If a failure of some elements or chains, the problem probably lies in a blown fuse or bad grounding as frequently one safety lock protects some chains. | | 3. Problems with the operation of the electrical system are usually caused by the simple reasons, such as oxidised or unreliable contacts, blown fuse, fuse burned out or faulty relay. Visually check the condition of all safety locks, wires and sockets in the affected circuit before checking other elements of this circuit. | 4. The main instruments necessary to detect a fault in the circuit are:
- The tester or voltmeter (or lamp 12 V with connecting wires);
- Indicator lamp with power supply (or a device for checking the integrity of the chain);
- Ohmmeter (for resistance measurement);
- accumulator battery;
- Probes with wires;
- Cap the wire, preferably with a circuit breaker or fuse, which can be used to check the wiring or elements of the electric equipment. | | 5. To detect a bad connection or the fault location (usually because of a bad connection or dirty, or damaged insulation) wires can be shaken by hand to see if the circuit does not go out of operation at wire movement. In this way, one can find a point with fragile connector or the point at which a short circuit occurs. | | 6. In addition to the problems associated with an unreliable connection, the electrical circuit may have two other major fault - an open circuit or short circuit. | | 7. The open circuit may be caused by the disruption of any wires or absence of compound in the chain, which would prevent the flow of current. Open circuit will cause the failure of any item of electrical equipment, but will not result in a blown fuse protecting the circuit. | | 8. Problems with the short circuit caused by the closure of the circuit, which leads to the fact that the current flowing through the circuit begins to flow in the other circuit, and usually goes to "mass". Short circuit is usually caused by rupture of isolation, allowing the power supply wires to touch any other wire or grounded element such as a body. Short circuit causes a blown fuse, which protects the corresponding chain. | | 9. Before finding the source of a fault or during repairs in the electrical system, be aware that different types of cables have a different color. | | 10. To detect open circuit, connect one lead of a control bulb to the negative terminal of the battery or the "weight" of the car. | | 11. Connect the second probe to connection in a checked chain, preferably located as close as possible to the battery or fuse. | | 12. Apply power to the circuit. Do not forget that in some circuits the voltage is applied only when you turn the key in the ignition lock in certain position. | | 13. If pressure is present (about what the lighted up will testify control light or voltmeter indications), it means that part of the chain between the compound and the battery is working. | | 14. Continue to check the rest of the circuit in the same way. | | 15. When the point is found where the voltage is absent, it means that the source of the fault lies between this point and the previous point, where the voltage is present. Most of the problems associated with poor connection. | | 16. The negative terminal of the battery is connected to the "weight" of the car - to metal engine / transmission and body of the car - and the majority of systems of electrical equipment are designed to fit a piece of equipment only one power cord, and current returns through the metal body of the car. This means that the electrical mounting element and the vehicle body are part of the electrical circuit. Therefore, bad or oxidised fastening can cause a large number of problems in the electrical system from the total yield of the chain failed to unreliable it works. In particular, bulbs can burn dimly (especially if you include another circuit using the same point of the earth), motors (eg wiper motors or the radiator fan) can work slowly and the inclusion of any chain can influence the work of other chain. Note that on many cars connecting earthing strips between the different units of the automobile, for example, between the engine / transmission and body, that is, usually when there is no metal between the contact elements due to the use of rubber mounts, etc. | | 17. To verify the reliability of grounding disconnect the battery and connect one lead of an ohmmeter to the "weight" of the car. Connect the other test lead to a wire or ground point to be tested. Resistance recorded by an ohmmeter should be equal to zero, otherwise, check the connection as follows. | | 18. If you think that the connection is not in order, disassemble connection and smooth out to pure metal contact surface and the surface of the terminal wires or grounding element. Completely remove dirt and corrosion, and then using a knife to remove the layer of paint in order to obtain reliable metal-to-metal connection. At assemblage reliably secure connection; When installing the wire terminals using toothed washers between the plug and the body. After connecting to prevent corrosion, apply a connection layer of vaseline or silicone grease. |
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CIRCUIT BREAKERS
Fuses serve to break the circuit when the current reaches a certain value, in order to protect components and wires, which could be damaged too much current. The sharp increase of the current is typically caused by a malfunction in the circuit, often short-circuited.
Legend circuits protected by fuses given in the fuse box cover.
Before removing the fuse, turn off the appropriate circuit (or lighting), and then remove the fuse from the contacts. Inside the fuse wire should be visible; If the fuse is blown, the wire is torn or melted.
Always use fuses of the required power. Never use another power fuse and replace it with something else. Do not replace the fuse more than once, do not eliminate the source of the fault. The current protected fuse is indicated on top of the guard: Please note that the fuses have different colors for easy identification.
If the fuse blows immediately after replacement, do not replace it again until you install or remove the cause of the fault. In most cases, the cause of the fault is a short circuit, caused by poor insulation. If the safety lock protects some chains, try to look for the chain, which caused the fuse blows, including each of the circuits on the line (if possible). Always have a car kit of spare fuses of various capacities. They should be fixed at the bottom of the fuse box.
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