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How to Tell if Your Car Battery Needs Replacing

Model: (Various brands) Various
Part: Battery

This video provides interesting technical insights to understand a key concept: the open circuit voltage is not enough to judge the health of a car battery. Here’s how to tell if the battery really needs changing: the engine struggles to turn over, prolonged cranking; dim lights when attempting to start; Start & Stop not functioning; intermittent electronic errors; battery over 4 to 5 years old. The resting measurement should be 12.6V at full charge: 12.4V at 75% charge; 12.2V indicates a flat or deteriorated battery. Visually check for swelling of the casing, heat damage, or leakage, which indicates corrosion on the terminals; if the battery is serviceable and you see exposed plates. A professional load tester is essential, measuring internal resistance that increases with age, simulating a load as during starting, calculating the cold cranking amps, and if it is below 50%, then the battery needs replacing. Modern AGM/EFB batteries have different charge voltages, and if replaced, you must reprogram the ECU with an OBD tool. Remember that a standard battery in place of an AGM will deteriorate in a few months.

Posted on 19 August 2026 by ScegliAuto

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How to Open a Stuck Boot on the Peugeot 407?

On the Peugeot 407, the boot may become stuck, possibly due to a problem with the control button or the lock actuator. In such cases, you can perform an emergency opening by following the simple procedure shown in this tutorial. First, open the rear doors, then lower the seat back by operating the release lever. Next, go inside the boot, locate the lock, and manually operate it using a flathead screwdriver. The boot will then be free to open.

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