How Keyless Entry Systems Continuously Use Battery Power

Cars today utilise a keyless entry system for a seamless driving experience. Smart access is popular because users can lock, unlock and secure their car without a physical key.

Many users who prefer the smart access feature don’t realise the system continues to drain power after the car is off. The system has to monitor the smart key, check for signals and keep the system's electronics on.

Over time, the system starts to take a toll on the battery, especially if the car is not driven regularly.

How Keyless Entry Systems Work

The keyless entry feature depends on wireless communication between the smart key and the car's system. Once the key fob is in the vicinity of the car, it sends a signal and the car’s system checks whether the signal was an authorised system access. The system then enables the user to unlock the doors, start the car, or open the trunk.

This communication is not a one-time check and is not activated by the driver. The system does this continuously to remain alert in case the driver comes in proximity to the key fob.

Why Keyless Entry Systems Use Battery Power Constantly

Keyless entry battery drain is mainly caused by the system’s constant signal check. The system has to keep searching for an authorised key, which requires a constant and steady drain on the battery.

Some electronic control units can stay active in standby mode. These units may control smart locking, anti-theft, and access controls.

Security and convenience features may also run quietly in the background. While the power use may seem small, it can add up over hours or days.

Factors That Increase Car Battery Drain

• Holding the key fob too close to the parked vehicle. If the key is nearby, the vehicle may communicate with it more often than necessary.
• The longer the vehicle sits, the worse the situation can become for the battery recharge. Vehicle batteries don’t have enough time to recharge on the commute, with the vehicle sitting for prolonged periods. Old vehicle batteries have an even lower reserve capacity and are worse in this situation.
• Connected vehicle features such as embedded GPS, mobile apps, security notifications, and vehicle diagnostics can drain the battery when the engine is off.

Signs Your Keyless Entry System May Be Affecting Battery Health

• If you frequently see low battery warnings, the vehicle may have electrical system issues.
• Slow engine cranking during startup is another sign that the battery is weak.
• It can even seem like the battery dies quicker than it should. In some cases, repeated jump-starts could mean the need for a car battery replacement soon.

How Professionals Minimise Battery Drain Issues

The first step in addressing battery drain is to locate the cause, which a professional can do easily. They can all measure battery voltage, charging performance, and battery health. This helps confirm whether the issue is with the battery or another electrical component.

Some vehicles may just need a software update to their electronics. A full diagnostic of the electrical system can identify a parasitic drain and hopefully prevent sudden breakdowns.

Conclusion

It is easier and safer to drive a modern car with a keyless entry system, but it can drain the car's battery. Understanding how battery drain works helps car owners better care for their vehicles.

Regular inspections and preventive maintenance can reduce the risk of sudden battery failure. Get your vehicle checked by AIS Windshield Expert’s trained professionals for a timely car battery replacement or necessary repairs.