What are the reasons for a car making a clicking sound but failing to start when igniting?

[LeColeman]

When a car makes a clicking sound but fails to start during ignition, it may be due to a "broken cell" fault in the battery. The common reasons for a car failing to start are as follows: 1. Battery depletion: Battery depletion is one of the most common reasons for a car not starting. Apart from the battery's own quality and lifespan issues, depletion is usually caused by improper use by the owner, such as forgetting to turn off the headlights when parking or using too many external electrical devices. A car failing to start due to battery depletion typically manifests as the starter not working or having significantly insufficient speed during ignition. 2. Smart key battery depletion: This issue only applies to cars with a keyless start function. When the car key is nearby, pressing the start button fails to start the car, and the smart key fault light on the dashboard remains lit, this indicates that the smart key battery is depleted. Some car models with a keyless start function also retain a traditional key start design, allowing the car to be started with the key when the smart key battery is depleted.