Automobile circuit, what does that 30, 15, 3 1 x mean?

1 and 30 stand for constant current and battery power supply, which is directly supplied by the battery.

2.3 1 stands for ground wire, which is ground wire.

3.x is the live wire controlled by the ignition switch and passing through the unloading relay, usually a high-power electrical appliance, that is, IG electricity. Such as wipers, heaters, air conditioners and other equipment.

4. 15 and x are the live wires of the ignition switch, which are usually on.

Extended data

Types of automobile circuit diagrams

1. circuit diagram: it is a traditional expression of automobile circuit, which is formed by connecting automobile electrical appliances from power supply to switch to ground one by one in the actual position of the automobile.

2. Circuit schematic diagram: First, according to the circuit principle, connect the systems from top to bottom reasonably with concise graphic symbols, and then arrange the systems reasonably.

3. Circuit connection diagram: used to show the connection relationship between each terminal of electrical equipment and each pin of relay.

4. Wiring diagram: Assemble the wires of related electrical appliances into a wiring harness for easy installation in the car.

5. Component location map: It is a drawing of the location of electrical components.

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