What is the reason why the remote key cannot open the trunk?

[HarperFitz]

The reason the remote key cannot open the trunk is insufficient power of the remote, resulting in a weak signal that the receiver cannot detect. The basic components of a remote key consist of the following two points: 1. Transmitter: Composed of a transmission switch, transmission antenna, integrated circuit, etc., it contains an identification code storage circuit and an amplitude modulation circuit, with a button-type lithium battery installed on the opposite side of the circuit. The transmission frequency uses radio waves, and pressing the transmission switch button once sends a signal. 2. Receiver: After the transmitter sends the identification code using shortwave modulation, it is received by the car's shortwave antenna and enters the shortwave high-frequency amplification processor of the receiver's electronic control unit via a distributor for demodulation, where it is compared with the demodulator's identification code.

[VanOscar]

I often hear friends complain that the remote key can't open the trunk, which is quite common. A dead key battery is the main reason—the battery typically lasts two to three years before draining, causing the signal to weaken and fail. Environmental interference is also annoying, such as near high-voltage substations or large electronic devices, where signals get disrupted and can't reach the car. Faults in the trunk lock itself are also common, like the lock mechanism getting jammed by dust or the motor burning out. Oh, and poor key button contact is often overlooked—keys that have been dropped a few times are prone to this issue. If pressing the button repeatedly doesn't work, try manual unlocking as an emergency measure, then get it checked promptly to avoid forcing the trunk open and damaging parts.

[Jasper]

I usually approach such issues in three steps: First, check the key status by using a spare key to confirm if the key itself is faulty. Second, eliminate signal interference by trying a different location, such as moving away from transformers or LED screens. Third, inspect the vehicle system by observing the dashboard for any fault indicators or attempting to start the vehicle to rule out battery issues. Mechanical faults should not be overlooked either; for example, a deformed trunk latch or loose spring can prevent the reception of the opening signal. If the vehicle has an aftermarket electronic anti-theft device installed, it may conflict with the original car system, requiring signal rematching. In emergencies, you can access the trunk by folding down the rear seats and pulling the emergency release lever from inside the car.

[PaulDella]

Last week, I experienced this issue myself—I couldn't open the trunk with the key when driving to the supermarket. It turned out that rainwater had seeped into the lock hole, causing rust and jamming the mechanical lock cylinder. Actually, daily maintenance is crucial. Worn rubber seals can allow rainwater to penetrate the lock mechanism, and sweat on the key buttons can corrode the contacts. A repair technician once told me that many cars start experiencing wiring aging after about ten years, with oxidized connectors leading to poor contact. Now, I've developed the habit of regularly cleaning the lock hole and using WD-40 to maintain lubrication. Avoiding keeping the key in the same pocket as my phone also helps reduce signal interference. In the end, I found that replacing the button battery was the simplest solution.

[DelBrady]

Don't panic when encountering this situation. Check a few simple things: the key indicator light can show battery status; press the button within half a meter of the vehicle to rule out distance issues; see if the doors can be unlocked remotely to check if the whole system is working. It's important to carry a spare key daily for emergencies. Ladies should note that magnetic clasps in bags may interfere with signals, so it's recommended to keep the key separate. Cold weather reducing battery activity is also a reason—warming the key before trying might help. Custom metal key cases can block signals; switching to a silicone cover solves this. If all else fails, use the mechanical key to unlock.