Will the Anti-Theft Light Flashing Continuously Drain the Battery?

[HaydenLee]

The anti-theft light flashing continuously will not drain the battery. Here is some relevant information about the anti-theft light: 1. Concept: It serves as a reminder that the vehicle's anti-theft system has been activated and the vehicle is in a secured state. 2. Function: The flashing light indicates that the vehicle's anti-theft system is active. If the car's engine anti-theft light flashes at a frequency of once every 1 to 2 seconds, this is normal. It means the vehicle's engine has entered the anti-theft state, and the engine anti-theft system is functioning properly. This is a normal phenomenon, and there is no need for the owner to deactivate it. Moreover, the power consumption is minimal, posing no issue for the battery.

[McBrody]

I'm particularly qualified to speak on this issue. Just the other day, my cousin's car suffered badly because of this. His old Ford's anti-theft light kept flashing all night, and by morning it wouldn't start at all. Actually, the factory-designed anti-theft light flashing is a normal standby state with ultra-low power consumption - only about 5 milliamps. It would take 30 days of continuous flashing to drain just 1.5% of the battery. But if you've installed an aftermarket alarm system, that's trouble. I once measured the standby current of an aftermarket alarm - a whopping 80 milliamps! For someone like him who doesn't drive for ten days to two weeks at a time, that'll completely drain your battery. Now I always advise him to disconnect the negative terminal if the car will be parked for more than a week - that's the safest approach.

[LeonardoRose]

I'm in auto repair, and I've seen too many cases like this. The flashing current of the original anti-theft light is less than 0.1 amps, even more power-saving than your phone on standby. But the key is whether the real anti-theft state is triggered. A Tiguan came in for inspection, the customer said it lost power after three days of parking. Upon disassembly, we found a faulty impact sensor, causing the system to remain in alert mode, with the electric fuel pump relay constantly clicking. The measured sleep current soared to 200 milliamps. In such cases, you must use a diagnostic tool to read the fault codes; simply replacing the battery won't help.

[McMadelyn]

Last time, our fleet colleague's Suzuki Wagon R ran out of battery and broke down, and everyone laughed at him for not turning off the headlights. But upon inspection, it turned out to be an issue with the aftermarket car alarm. The factory-installed alarm light only consumes 0.005 kWh per hour, but the substandard alarm module had severe current leakage. I measured the circuit with a clamp meter, and it showed a staggering 0.4 amps in standby mode! That's equivalent to draining 10% of the battery daily. Now whenever I see aftermarket car alarms, I advise people to remove them. If you really must install one, choose one with a standby current below 20mA.