What do IG1 and IG2 represent in automotive circuits?
2 Answers
The ignition switch has four positions: lock (off position), acc (radio position), on (ignition position), and start (starting position). Both IG1 and IG2 belong to the on position. Below are the relevant explanations: 1. After locking the car, the key will be in the lock state, which not only locks the steering wheel but also cuts off the power supply to the entire vehicle. 2. The acc state supplies power to some of the vehicle's electrical equipment, such as the CD player and air conditioning. 3. During normal driving, the key is in the on state, where all circuits in the vehicle are operational. 4. The start position is for engine starting, and after starting, it automatically returns to the normal state, which is the on position.
When I first started driving, IG1 and IG2 really confused me. IG1 is the first position when you turn the key, also called the ACC position, which powers the car's radio, phone charger, and cigarette lighter. IG2 is the second position or the start position, mainly used for igniting the engine and running engine-related systems. Once during a camping trip, I plugged the car fridge into IG2 by mistake and left it running without starting the car, draining the battery overnight. I had to call for help to get out of that mess. So, understanding the difference between these two is quite important, especially before long drives—check your electrical connections. I recommend new car owners to flip through the car manual; it has diagrams that clearly explain the positions. During regular maintenance, make sure the fuses are intact and keep the wiring dry to avoid rust, which can save you a lot of trouble.
