What is the reason for the Mercedes-Benz GLA prompting to add coolant?

[DelDawson]

Mercedes-Benz GLA prompting to add coolant is due to the lack of antifreeze in the cooling system. The role of coolant: Most cars use water-cooled engines, which rely on antifreeze for heat dissipation. Antifreeze circulates in the engine through two paths: a major cycle and a minor cycle. When the engine is just started, the antifreeze performs a minor cycle, during which it does not pass through the radiator, allowing the engine to warm up quickly. Once the engine reaches its normal operating temperature after running for a while, the antifreeze switches to a major cycle, passing through the radiator to dissipate heat, thereby maintaining the engine within its normal operating temperature range. Precautions for replacing antifreeze: Replace the antifreeze regularly, and ensure that the old antifreeze is completely drained from the cooling system during replacement.