Visual diagnosis

When the truck circuit breaks down, some abnormal phenomena, such as smoke, sparks, abnormal noise, stink and fever, may occur. These phenomena can be observed directly and the location of the fault can be judged.

Circuit breakage method

When a fault occurs in truck circuit equipment, it can be judged by circuit breaking method. After disconnecting the circuit section suspected of the fault, it can be observed whether the fault still exists in electrical equipment, so as to determine the location and cause of the fault.

Short circuit method

If there is a breaking fault in the truck circuit, it can also be judged by short circuit method. The circuit suspected of breaking fault can be shortened by the screwdriver or wire. The change of instrument pointer or the working condition of electrical equipment can be observed to determine whether there is a breaking fault in the circuit.

Test lamp method

The test lamp method is to use a vehicle lamp as the test lamp to check whether there is a circuit breakdown.

Meter method

Observe the indicators of ammeter, water temperature meter, fuel meter and oil pressure gauge on the instrument panel of Baotou Beiben Heavy Truck Parts, and judge whether there are any faults in the circuit. For example, when Baotou northbound heavy truck parts engine is in cooling state and ignition switch is switched on, the thermometer pointer is fixed at full scale position, indicating that the thermometer sensor is faulty or that the line has a tie-up.

Fire Test Method for Low Pressure Iron Layer

Remove the wire end of the electrical equipment and judge the spark produced by the metal part of the truck. This method is relatively simple and is often used by truck electricians. There are two kinds of fire test methods: direct and indirect. Particularly noteworthy is that the fire test method can not be used in electronic line trucks.

Direct iron hitching: It is the direct iron hitching without overload to produce strong sparks. For example, if we want to judge whether the circuit from ignition coil to storage battery is faulty, we can remove the wiring connecting Baotou to the ignition switch of heavy truck parts northbound from ignition coil, scratch on truck body or frame, and if there is strong spark, the circuit is normal; if there is no spark, the circuit in this section appears to be broken. 。

Indirect tie-up method: It is to judge whether the line or load is faulty by the weak spark generated by the tie-up of a certain load of truck electrical appliances. For example, if there is spark, the traditional ignition system disconnector connection line will be tied up, indicating that the line is normal; if there is no spark, the circuit will be broken.

High pressure fire test

The high voltage circuit is tested by iron, the spark condition is observed, and the working condition of the ignition system is judged. The specific method is: take off the high-voltage wire of ignition coil or spark plug, align it with spark plug or cylinder head, distance is about 5mm, then turn on the starting switch, turn the engine, see its spark jump. If the spark is strong, sky blue, and the fire jump is loud, it indicates that the ignition system works basically normally; on the contrary, it indicates that the ignition system works abnormally.

Finally, we should remind you that if you are not familiar with the circuit, or to let professionals overhaul, self-repair circuit must pay attention to safety.