A relay is basically an electrically operated switch. It takes a relatively small electrical signal and uses that to control a much larger one. Think of it like a gatekeeper – a little nudge opens a big door. It allows a low – current circuit to control a high – current circuit. They handle things like headlights, the starter motor, the horn – anything that needs a lot of power to run. They’re scattered all over the vehicle, mostly in the under – hood electrical center, but sometimes you’ll find them in the body control module area too. They're part of a circuit, sitting between the power source and the device they’re controlling. They don’t make the power, they just direct it where it needs to go. They’re often used where running a high – current wire directly from a switch to the device would be impractical or unsafe. They protect the wiring and other components. Without a relay, those high – current devices would put a huge strain on your switches and wiring, leading to overheating and potentially a fire. It acts like a shield for the sensitive parts of your system. You’ll notice if a relay goes bad because the associated device – a headlight, the starter, whatever it is – will stop working, or might work intermittently. Sometimes you'll get nothing at all. We carry a pretty good selection of these at Fixparts Online, and matching the right one is key. It’s usually labeled with a part number that makes it easier to find the correct replacement. Guaranteed quality: Relay (MPN A9909820600) includes a 12-month warranty!

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