How to repair car wiring harness

　　The maintenance of automotive wiring harnesses is a meticulous and important process that directly affects the normal operation of the automotive electrical system. The following are the main steps and precautions for repairing automotive wiring harnesses:

　　1、 Preparation before maintenance

　　Understanding the wiring harness layout: Before maintenance, it is necessary to understand the layout and direction of the vehicle wiring harness in order to quickly locate the fault point.

　　Preparation tools: Prepare the necessary tools for maintenance, such as multimeters, test lights, wire strippers, crimping tools, heat shrink tubing, insulation tape, etc.

　　2、 Visual inspection

　　Appearance inspection: Firstly, inspect the appearance of the wiring harness and observe for any signs of damage, aging, burning, corrosion, etc. Pay special attention to the connection parts of the connector to see if there is any looseness, detachment, or corrosion.

　　Function check: By operating relevant electrical equipment, observe the working status of the wiring harness, such as whether the lights, speakers, air conditioning, etc. are working properly.

　　3、 Use testing tools to check

　　Multimeter testing:

　　Resistance detection: Disconnect the tested wire, select the appropriate range, and use a multimeter to measure the resistance value of the wire. If the resistance value exceeds the standard value, it indicates that there may be an open circuit or poor contact in the wire.

　　Voltage detection: When the circuit is powered on, measure the voltage values at each point in the wiring harness to determine if the voltage is normal and if there is a short circuit or open circuit.

　　Test lamp inspection: Use a test lamp to check for open circuit faults in the wires. During testing, be careful not to exceed the power of the test lamp to prevent damage to the controller due to overload. By testing the lamp, it is possible to visually observe whether the circuit is conducting.

　　4、 Jumping method

　　Short circuit the suspected faulty line with a wire, and then observe the changes in the instrument pointer or the working condition of the electrical equipment to determine whether there is an open circuit or poor contact fault in the circuit. This method can quickly locate the fault point, but safety precautions need to be taken to avoid the danger of short circuits causing fires and other hazards.

　　5、 Replace or repair

　　Replace the wire: If the wire is severely damaged or cannot be repaired, a new wire needs to be replaced. When replacing, the correct wire specifications and colors should be selected according to the requirements of the circuit diagram.

　　Repair connector: If the connector is damaged, it can be repaired. When repairing, it is necessary to clean the dirt and corrosive substances inside the connector, check whether the pins and terminals are damaged, and replace them if they are damaged. Then reconnect the connector to ensure a secure and reliable connection.

　　6、 Bandaging and fixation

　　Wrap the wiring harness: After repairing or replacing the wires, it is necessary to wrap the wiring harness. When wrapping, the wiring harness should be branched according to its original form, and the exposed part should meet the specified length. The joint should not have any exposed parts. Insulation tape or heat shrink tubing can be used for wrapping.

　　Fixed wiring harness: The wiring harness should be fixed using clamps, trip pins, and other fixing devices to prevent loosening and wear. At corners or parts with relative movement, the wiring harness should be loosened appropriately to avoid being pulled too tightly and causing breakage.

　　7、 Testing and Validation

　　After the maintenance is completed, it is necessary to conduct comprehensive testing and verification of the vehicle to ensure that the electrical system returns to normal operation. Verification can be carried out by operating relevant electrical equipment, observing instrument indications, and other methods.

　　In summary, the maintenance of automotive wiring harnesses requires careful, patient, and professional skills. During the maintenance process, it is necessary to follow certain steps and precautions to ensure the quality of maintenance and driving safety.