What is the battery model for BMW keys?
2 Answers
BMW key battery model is CR2450. Basic principle of BMW remote key: The key emits weak radio waves, which are received by the car antenna. The electronic control unit (ECU) identifies the signal code, and then the system's actuator (motor or electromagnetic coil) performs the lock/unlock action. This system mainly consists of two parts: transmitter and receiver. Steps to replace a dead key battery: Flip the key to its back side, locate and press a small button; pull the key handle upward to remove it, revealing the metal mechanical key; use this mechanical key to pry open the key cover - once a gap appears, apply slight force to open it; remove the old battery and replace it with a new one; reassemble the key cover and reinsert the mechanical key to complete the replacement.
The battery model for BMW car keys is typically CR2032. Many people ask about this because, after driving a BMW for years, I've encountered several instances of key malfunction. The first time it happened, I was really worried and thought I needed to replace the key, only to find out the battery had simply died. This CR2032 battery is a 3-volt lithium coin cell, easily available at supermarkets, hardware stores, or on platforms like JD.com, and it's quite affordable, usually around ten yuan each. Most BMW models, such as the mainstream 3 Series, 5 Series, and X Series, use this battery. When replacing it, use a small flat-head screwdriver to gently pry open the key casing—avoid using excessive force to prevent damaging the plastic clips. Ensure the battery is inserted with the positive side facing outward; it won’t work if installed backward. After replacement, test the remote range to ensure it functions properly. It’s recommended to check the battery status every two years to avoid sudden key failure during trips.
