What are the reasons why BYD does not detect the key?
4 Answers
BYD does not detect the key for the following reasons: Insufficient key battery: The battery used in the remote key is generally an ordinary button battery, with a rated working voltage of about 3.3V. Under normal circumstances, the service life can generally reach 2 years. Signal interference: Placing the key together with devices such as mobile phones, laptops, and power converters. Since radio devices such as mobile phones, laptops, and power converters emit wireless signals that interfere with the smart key, the key should be kept away from the above devices when in use. Antenna problem: There is a problem with the antenna inside the rear window glass, and the signal cannot be received. You can pay attention to whether the antenna signal amplifier is working properly and whether there is a film that causes signal shielding.
I recently encountered the issue of my BYD not detecting the key, which was quite frustrating. The most common reason is that the key battery is running low—these small button batteries typically need replacement every two years. If replacing the battery doesn’t solve the problem, the key itself might be damaged, as drops or water exposure can disrupt the internal circuits. Don’t overlook the parking location either; nearby high-voltage lines or large electronic devices can create signal interference. Additionally, if the car’s receiver module is faulty, it won’t recognize the key, requiring a professional diagnostic at a 4S shop. It’s also important to avoid storing the key near phones or credit cards, as electromagnetic interference can weaken the signal. I’ve found that pressing the key against the start button for a few seconds can sometimes wake up the system—a handy trick in emergencies.
When the key is not detected, don't rush to call a tow truck. First, check the key's battery level—it's easy to replace it yourself; just buy a CR2032 battery from the supermarket. Then, pay attention to the operation sequence: try pressing the brake pedal while placing the key against the start button, as many cars have an emergency sensing position. Here's another tip: place the key at the bottom of the cup holder or in the center console storage compartment—these are signal enhancement zones. If you've recently installed electronic devices like a dash cam, there might be signal interference that needs troubleshooting. Over time, an aging car battery can also cause the receiver to malfunction; just check the voltage with a multimeter. If all else fails, use the spare key for a comparison test to quickly determine whether it's a key issue or a car malfunction.
This issue is usually related to usage habits. Many people tend to casually throw their keys into the trunk, where the metal environment can block the signal; placing them in the inner pocket of a suit or a thick wallet compartment can also affect recognition. Be especially cautious in underground parking lots of large shopping malls, as their anti-theft systems often interfere with car key frequencies. Avoid exposing the key to direct sunlight or getting it wet, as the circuit board is particularly delicate. I've seen cases where using alcohol to clean the key corroded the chip. Here's a small reminder: some BYD models require key re-matching after a system update, and this software issue can usually be resolved by restarting the car's infotainment system. It's quite useful to keep a spare key battery in the glove compartment.
