What are the reasons why BYD's keyless start cannot detect the key?

[LeilaLee]

Frequently placing the car key near electronic devices such as mobile phones, computers, or televisions can cause interference with the low-intensity radio waves in the key. Additionally, strong radio waves from nearby sources like TV towers, airports, or power plants can also lead to the failure of the one-button start function. Below are some solutions for when the key cannot be detected: 1. Dead key battery: If the one-button start fails to detect the key, the first thing to check is whether the car key has enough battery power. Try replacing the key's battery and then attempt the one-button start again to see if it returns to normal. If the issue persists, it might be due to poor battery contact, in which case the car key may need to be repaired. 2. Spare key: You can also try using the car's spare key to determine if the first key is faulty and causing the issue. If the spare key works, it indicates that the first key is defective. If the spare key also fails to work, further analysis based on other scenarios will be necessary.

[SanLukas]

I've been driving BYD for over a decade and have encountered several keyless start failures. The most common issue is a dead key fob battery - these small batteries typically last one to two years, and insufficient power will definitely prevent the car from detecting it. Another possibility is strong nearby interference, like the anti-theft access systems in mall underground parking lots, or having your phone placed too close which can also disrupt the signal. My suggestion is to first replace the key fob battery with a new one. If that doesn't work, try changing locations - for example, place it in the dedicated induction area in the center console cup holder. Additionally, physical damage like dropping the key or moisture exposure could cause issues, so check the casing for cracks. I keep a mechanical key as backup for emergencies, but for actual repairs you'll need to visit the 4S店 to reprogram the system.

[Alina]

I've encountered this key detection failure several times. Once I found it was because my phone and car key were stuffed in the same pants pocket, causing electronic interference. BYD's keyless system relies on low-frequency signal connection, which has limited range - typically within 1.5 meters of the car door. If the failure occurs frequently, you might need to check if the key button is stuck or if the door's receiving antenna is loose. Temporary solutions include taking out the key and pressing the unlock button to wake up the signal, or using the mobile app for remote start. However, I don't recommend disassembling the key yourself - the internal circuit board is quite delicate. Last time my colleague tried fixing it himself and short-circuited the chip, costing over 800 yuan to replace the whole set.

[StHeidi]

Last time when I was driving my kid to school, the car suddenly couldn't detect the key, which made me sweat with anxiety. Later I found out the car key was blocked by other metal objects - coins and keychains mixed together in the wallet can interfere with the signal. BYD's smart key requires two-way authentication, and unstable car battery voltage can also affect recognition, especially during cold starts in winter. If this happens, don't panic - first try holding the start button for 10 seconds to force restart the system, or place the key close to the start button to try emergency mode. The safest approach is to keep a spare key in the car in advance, but remember to lock the doors properly to prevent theft.

[DavidLee]

Keyless start failure is mostly caused by communication link issues. BYD's PEPS system relies on 125kHz low-frequency signals, which are prone to interference when near high-voltage lines or signal towers. The triaxial accelerometer inside the key may lose sensitivity due to prolonged vibration, especially for owners who frequently keep it in their pocket while running. Tests show that in strong magnetic fields, the vehicle receiver may delay response by over 20 seconds. During repairs, use a diagnostic tool to read fault codes from the body control module—common ones include B1678 (key ID mismatch) or U01487 (communication interruption). Regularly cleaning the key contacts can prevent many issues, but avoid using corrosive cleaners on the circuit board.

[OLuke]

This issue typically has four causes: depleted key battery, faulty vehicle receiver module, environmental electromagnetic interference, or system software bugs. I recommend first ruling out simple scenarios, such as testing the battery voltage with a multimeter - replace if below 2.8V. If failures occur during rainy weather, it might be due to moisture in the antenna connector; check the seal ring of the receiver box on the left side of the trunk. Remote updates to the vehicle's infotainment system can sometimes fix recognition issues, but remember to keep the engine running during updates. Here's an obscure tip: wearing certain anti-static workwear can cause signal attenuation - I once encountered a technician in protective clothing who couldn't start the car during inspection.