HOW TO DETECT THE SHORT-CIRCUIT FAULT OF THE TERMINAL?

Definition of terminal

The terminal is used to facilitate the connection of the wires. It is actually a piece of metal sheet enclosed in an insulating plastic. There are holes at both ends to insert the wires. There are screws for fastening or loosening. They need to be connected and sometimes need to be disconnected. At this time, they can be connected with terminals and can be disconnected at any time without having to weld or entangle them, which is very convenient and quick. And it is suitable for a large number of wire interconnections. In the power industry, there are special terminal blocks, terminal boxes, all of which are terminal blocks, single-layer, double-layer, current, voltage, ordinary, breakable and so on. A certain crimping area is to ensure reliable contact and to ensure sufficient current can be passed.

In the process of using the terminal, if it encounters a short-circuit fault, it will affect people's use, then in the actual production process, what methods can be used to solve the short-circuit fault of the terminal? The following text will introduce some measures.

The failure of the wiring harness terminal may also be caused by a short circuit between the wiring harness and the vehicle body (ground wire) or inside the switch concerned. Before checking, you should check whether the terminals of the vehicle body are firmly fixed, and then you can test according to the following steps:

1. Check wiring harness continuity

Remove the control terminals on both sides of the control computer ECU and the sensor, and then measure the resistance between the corresponding terminals of the terminals. If the resistance is not greater than 1 ohm, the wire is normal for the next inspection. When measuring the resistance of the wire, it is good to shake the wire harness in both vertical and horizontal directions to improve the accuracy of the measurement. At the same time, pay attention that most wire terminals and multimeter meter bars should be inserted from the rear of the connector, but the sheathed waterproof terminal bar can not be inserted from the back, because the terminal will be deformed if you are not careful when inserting it.

2. Check the resistance value of the short circuit. 

Remove the wiring harness terminals on both sides of the control computer ECU and sensor, and then measure the resistance between each terminal block of the connector on both sides and the body. During the measurement, one end of the meter bar is connected to the car body by iron, and the other end is measured on the harness connector on both sides. If the resistance value is greater than 1 ohm, there is no short circuit between the harness and the car body.

3. Terminal appearance and contact pressure inspection

First remove each terminal one by one, check the connector terminals for rust and dirt, and clean the rust and dirt. Then check whether the terminal piece is loose or damaged, and whether the terminal is firmly fixed. When the terminal is gently pulled, there should be no looseness of the terminal. Conversely, if the plug terminal in one of the seat holes is easier to pull out than the other seat holes, the seat hole may cause poor contact failure during use.