Tutorial for Replacing Battery in Old Mercedes-Benz R500L Key
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Tutorial for replacing the battery in an old Mercedes-Benz R500L key is as follows: 1. Flip open the tab at the rear end of the key. 2. The mechanical key is located on the side of the key slot; press the internal gray button. 3. Push the rear end of the key upwards to create a gap, then remove the mechanical key. 4. Take out the rear end by hand to replace the battery. 5. After installing the new battery, reinsert the key holder to complete the battery replacement. Additional information about the Mercedes-Benz R500L key: 1. The lifespan of a Mercedes key battery is generally two years, while the original factory battery can last up to six years. 2. When the key battery is low, the Mercedes vehicle will provide two types of alerts: pressing the ignition switch will display a 'replace key battery' message on the dashboard; pressing the key's lock or unlock button will cause the indicator light on the key to dim or not light up.
Previously drove an old Mercedes-Benz R500L. When the key fob battery dies, replace it promptly to avoid the hassle of opening the car door. The battery model is usually CR2025, available for a few bucks at supermarkets or auto parts stores. The steps are super simple: there's a small groove or button on the back of the key fob—press lightly or use a small tool to pry open the casing. Be careful not to scratch the plastic. When removing the old battery, note the positive and negative orientation; insert the new battery of the same model with the positive side facing up. After reassembling the casing, test the remote function by pressing the lock and unlock buttons a few times to confirm. If opening the casing is difficult, don’t force it to avoid damaging the internal circuits. As a reminder, key fob batteries typically last one to two years, depending on usage frequency—it’s advisable to check them every six months. If issues persist after replacement, such as remote failure, it might be a chip malfunction. In that case, it’s better to get it checked at a 4S shop rather than delaying, as it could affect driving safety. I usually keep a spare battery in the glove compartment for emergencies.
