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Finding a source of malfunction in the electrical system

Insert a thin probe to the back of the connector connection, he referred to the required terminals - Connect the voltmeter to the probe.

The usual electric chain consists of an electric element, switches, relays, motors, fuses, fusible jumpers or breakers of this element, the wiring and connectors that connect the unit to the battery and the car body. For help in finding sources of electrical system malfunction, at the end of a management schemes of electric car.

Before trying to determine the source of the fault, first study the corresponding scheme of an electric equipment for representation reception about the elements established in this chain. The range of possible sources of malfunction can be narrowed if to check up functioning of other elements entering into the given chain. If some elements or chains fail simultaneously the problem obviously lies in the fuse common to these chains or elements, or contact with the car body.

Electric problems are usually caused by the simple reasons, such as the weakened or rusted sockets, absence of contact with the body of the car, blown fuse, the fused burnt through crosspiece or the faulty relay. Visually check the condition of all safety locks, wires and sockets in the failed chain before to start check of other elements.

If you intend to use test instruments, use the wiring diagram to determine which of the terminal clamps must be checked to detect the source of the fault.

The basic tools necessary to detect the source of the fault is the device for check of schemes or voltmeter (a bulb on 12 volt and the pair of wires with probes at the ends can also be used to carry out some checks); ohmmeter (for resistance measurement and the integrity checking circuits); the battery and a set of wires with probes; union wire, preferably with a circuit breaker or fuse, which is used for detour of checked wires or elements.

Check the voltage in the circuit should be carried out if the system is not functioning properly. Connect one probe of the tester to test circuits to the negative battery terminal or securely earthed element car. Connect the other probe to the connector on the circuit under test, it is desirable to ensure that close to the battery or fuse. If the lamp on the tester lights up, then this connector has a voltage, which means that a portion of the circuit between the battery and plug it in order. Continue to check the entire chain in the same way. When you find the point where there is no electricity, which means that the fault is located between this point and the last place where there was tension. In most cases, the cause of failure is a bad cable connection.

Do not forget that some chains receive power only when the ignition key is turned to ON or switch to start the engine.

To find the short circuit in the system, remove the fuse and connect a test lamp or a voltmeter to the place of the fuse. The circuit should not be the voltage. Move the wire from side to side and watch the indicator light. If the bulb lights up, it means that somewhere in this area there is a short circuit on "weight" of the car, most likely at the site where the insulation has worn off from the wires. The same test can be performed in other elements of the circuit including the ignition.

Checking the grounding should be carried out to verify the reliability of the electrical grounding element. Disconnect the battery and connect the probe control bulb with its own power source, such as the device to check the integrity of the chain to one end of the chain and the other probe to the second end of the chain. If the bulb lights up, it means that a good grounding. If the bulb does not light, poor grounding.

Check the integrity of the chain is carried out in order to check whether the circuit portion of the circuit or circuit element conductive. Disconnect the battery and connect the probe control bulb with its own power source, such as the device to check the integrity of the chain to one end of the chain and the other probe to the second end of the chain. If the bulb lights up, it means that the chain is not interrupted, and conducts electricity. The switches can be checked in the same manner.

Do not forget that in the electric car circuit current flows from the battery passes through the wires, switches, relays, etc. elements of electrical equipment (lights, motors, etc.). From them, the current flows in the vehicle body (ground), to which is returned to the battery. Any electrical failure caused by the interruption of the flow of current to the battery.

Check voltage

No voltage on the electrical element often caused by bad connection. Check the circuit path between the battery and the electrical element of integrity with a voltmeter.

Finding short-circuit

To check for a short circuit, remove the fuse and connect a test lamp or a voltmeter to the terminals of the fuse. Stress should not be. Move checked the wire from side to side. If the light comes on, it means that a short circuit occurs. The same test can be performed on any item of electrical equipment, even the switch.

Check for reliable grounding

Disconnect the battery and connect one wire of a control bulb with the power supply to the "mass" and the other wire to the "weight" of the checked element. If the bulb lights up, means, grounding is in order.

Continuity

To check the integrity of the chain of control, use a light bulb with the power supply. If the bulb lights up, it means that the chain is in order.

Finding a gap in the chain

If the chain does not pass current, most often caused by unreliable or compound oxides. Shake suspicious wire or connector connection - it can restore conductivity.