Toyota Camry

1996-2001 of release

Repair and car operation

The structure of electric chains of the car includes the consumer, switches, the relay and the wires connected on the enclosed scheme. Before starting troubleshooting it is necessary to study the scheme and to define a possible source of malfunction. For example, the problem of troubleshooting is considerably facilitated, if it will be possible to check serviceability of other consumers directly or indirectly connected to a suspected chain.

If refusal of several consumers is observed, the most probable cause is break of connection with weight or a safety lock peregoraniye. As a rule refusals of electric equipment are caused by weakening of contacts or their corrosion, a peregoraniye of a safety lock or a crossing point oplavleniye. Search of malfunctions as a rule is carried out visually, and also by means of a tester (voltmeter) or a control lamp which are connected between a site of a faulty chain and well smoothed out weight.

Search of a source of malfunction in electric equipment system

The typical electric chain consists of an element of electric equipment, switches, the relay, engines, the safety locks, burned-through crossing points or automatic switches and wires and connections which connect all elements among themselves and connect them to the accumulator and mass of the car.

Before the beginning of check of a faulty chain, in the beginning study the schematic diagram of this chain to understand from what elements it consists. The source of malfunction can be found quicker if to define, what of elements of this chain work normally. If some elements or chains fail at once, the problem, possibly, consists in the fused safety lock or bad grounding as often one safety lock is responsible for some chains.

Problems with work of system of electric equipment are usually caused by the simple reasons, such as the oxidized or unreliable contacts, the fused safety lock, the fused burned-through crossing point or the faulty relay. Visually check a condition of all safety locks, wires and connections in a faulty chain before the beginning of check of other elements of this chain. If you are going to use instrumentations, use schematic diagrams to define, what connections are necessary for checking for failure detection.

4. The main devices necessary for search of malfunction in a chain of electric equipment, are:

а) the device for verification of schemes or the voltmeter (or a bulb on 12 Volts with connecting wires);

б) a control bulb with the power supply (or the device for check of integrity of chains);

в) an ohmmeter (for resistance measurement);

г) accumulator;

д) щупы with wires;

е) a cap wire, it is desirable with the automatic switch or a safety lock which can be used for check of wires or electric equipment elements.

Before the beginning of search of malfunction with use of the control and measuring equipment, study schematic diagrams to define connection points.

For search of unreliable connection or a point of short circuit (usually because of the bad or polluted connection, or the damaged isolation) it is possible to shake wires by a hand to see, whether there is a chain out of operation at wire movement. Such way it is possible to find a point with unreliable connection or a point in which there is a short circuit. This method of check can be used along with other tests described in the following subsections.

Besides the problems connected with bad connection, the electric chain can have two other main malfunctions – gap existence in a chain or short circuit.

The gap in a chain can be caused by a rupture of any wire or absence of connection somewhere in a chain that will prevent a current current. The gap in a chain will cause refusal of any element of electric equipment in work, but will not lead to a peregoraniye of a safety lock of this chain.

The malfunctions connected with short circuit, are caused by short circuit somewhere in a chain that leads to that the current flowing on a chains, begins a leak on other chain, and more often, leaves on weight. Short circuit is usually caused by a rupture of isolation that allows a feeding wire to concern either other wire, or the earthed element, such, as a body. Short circuit leads to a peregoraniye of a safety lock of the corresponding chain.

Before search of a source of malfunction or at carrying out repair in electric equipment system, do not forget that various types of wires have various color.

Search of a rupture of a chain

For search of a rupture of a chain connect one of щупов a control bulb to the negative plug of the accumulator or mass of the car.

Connect the second щуп to connection in a checked chain, it is desirable located as it is possible closer to the accumulator or a safety lock.

Submit tension on a chain. Do not forget that tension is present at some chains only if to turn a key in the ignition lock in a certain situation.

If tension is present (about what the lit-up control bulb will testify or voltmeter indications), it means that the part of a chain between connection and the accumulator is serviceable.

Continue check of other part of a chain in the same way.

When you will find a point where tension is absent, it means that the source of malfunction lies between this point and the last point where tension was present. The majority of problems is caused by bad connection.

Search of short circuit

For chain check on existence of short circuit, in the beginning disconnect chain loading (loading is elements of electric equipment which consume the electric power, such as bulbs, engines, heating elements etc.).

Remove a safety lock of the corresponding chain and connect a control bulb or the voltmeter to plugs of connection of a safety lock.

Submit tension on a chain. Do not forget that tension is present at some chains only if to turn a key in the ignition lock in a certain situation.

If tension is present (about what the lit-up control bulb will testify or voltmeter indications), it means that in a chain there is a short circuit.

If tension is not present, but the safety lock nevertheless fuses at connection of elements of loading, means, is faulty any of these elements.

Check of reliability of grounding

The negative plug of the accumulator is connected to mass of the car – to metal of an engine / transmission and a car body – and the majority of systems of electric equipment are developed so that only one feeding wire approached to an element of electric equipment, and the current came back through metal of a body of the car. It means that fastening of an element of electric equipment and a body of the car are a part of an electric chain. Therefore, the bad or oxidized fastening can be at the bottom of a large number of malfunctions in electric equipment system, from a full exit of a chain out of operation before its unreliable work. In particular, bulbs can dimly burn (especially if other chain using the same grounding) is included, engines (for example, engines of screen wipers or the fan of cooling of a radiator) can slowly work and inclusion of any chain can influence work of other chain. Notice that on many cars connecting earthing strips between various units of the car are used, for example, between an engine/transmission and a body, usually when between elements there is no metal contact because of use of rubber fastenings etc.

For check of reliability of grounding disconnect the accumulator and connect one of щупов an ohmmeter to mass of the car. Connect the second щуп to a wire or a point of grounding which is necessary for checking. The resistance registered by an ohmmeter, should equal to zero; if is not present, check connection as follows.

If you consider that connection not as it should be, disassemble connection and smooth out to pure metal a contact surface and the plug of a wire or a surface of an earthed element. Remove completely dirt and corrosion traces, then, by means of a knife remove a paint coat to receive reliable compound of metal with metal. At assembly, reliably fix connection; at installation of the plug of a wire, use gear washers between the plug and a body. After connection, for prevention of formation of corrosion put on connection a layer of vaseline or silicone greasing.

Sockets

On considered cars multicontact sockets with plastic cases are applied. Reciprocal parts of sockets are kept by latches or the central screw (for example in sockets under the dashboard).

Latches are uncoupled by the thin flat tool. In some sockets of latches can be more than two. For chain check without a socket detachment щупы the device are entered from the back party of the socket against the stop into the plug.