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Auto | Under the Hood | Other Systems

Learn about the various electrical and other systems that lurk under your hood, including cooling systems, ignitions, wires, fuses and connectors.

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How does a radiator cap work?

The radiator of your car is composed of tubes that carry the coolant fluid, a protective cap that’s actually a pressure valve, and a tank on each side to catch the coolant overflow. Learn more about how a radiator cap works from this article.


 What is the difference between a normal lead-acid car battery and a deep cycle battery?

What is the difference between a normal lead-acid car battery and a "deep cycle" battery? I have a trolling motor on my boat and I don't see why I can't use my car's battery with it rather than spending another $80 on a deep cycle battery. See more »

 How does the thermostat in a car's cooling system work?

How does the thermostat in a car's cooling system work? I had to test my thermostat today and was amazed as I watched it! See more »

 What does the battery light on the dashboard mean?

The battery light on my car dashboard comes on whenever I am driving. How serious is this? The car seems to be working fine... See more »