How to replace the key battery for Mazda CX4?

[WilliamRose]

Steps to replace the key battery for Mazda CX4: 1. Take out the mechanical key, then wrap the test pen with a tissue and insert it into the middle gap, gently twisting it; 2. Continue inserting into the gap that was pried open, then forcefully pry it open to see the battery cover; 3. Continue using the test pen to pry in the middle, then take out the battery cover; 4. Remove the old battery, put in the new battery with the positive side facing up. The Mazda CX4 is a compact coupe SUV under the Mazda brand, with a length of 4637 mm, width of 1855 mm, height of 1531 mm, and a wheelbase of 2700 mm.