What an ABS sensor does
Each wheel has a sensor that tells the anti-lock brake system how fast it is turning. If one fails, the ABS light comes on and anti-lock braking may switch off, though your normal brakes still work.
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Short, plain-English guides to the parts and repairs we see most often. Read up before you visit, or bring your questions and we will walk through them together.

Pick a topic to narrow the list. Each guide takes a few minutes and explains what the part does, what goes wrong and what a repair involves.
Each wheel has a sensor that tells the anti-lock brake system how fast it is turning. If one fails, the ABS light comes on and anti-lock braking may switch off, though your normal brakes still work.
Pads press against the rotors to slow the car, and they wear down a little with every stop. Squealing, a longer stopping distance or a pad thinner than about a quarter inch means it is time for a check.
Brake fluid absorbs moisture over time, which lowers its boiling point and can cause rust inside the system. Replacing it on the schedule in your owner's manual keeps the pedal firm and the parts protected.
Spark plugs ignite the fuel and air mixture in each cylinder. Worn plugs can cause rough idling, hard starts and poor fuel economy, and they are usually quick to replace.
Coolant carries heat away from the engine and protects the cooling system from rust and freezing. Low or old coolant is one of the most common reasons an engine overheats.
The air filter keeps dust and debris out of the engine while letting in plenty of clean air. A clogged filter can reduce power and mileage, and it is one of the easiest parts to inspect.
The battery provides the burst of power that starts your engine and helps run the electronics. Slow cranking, dim lights or a battery more than a few years old are good reasons to have it tested.
The alternator recharges the battery and powers the car while the engine runs. A battery warning light, flickering headlights or a car that dies while driving can point to a failing alternator.
Each ignition coil turns battery power into the high voltage that makes a spark plug fire. A failing coil often shows up as a misfire, a shaking engine or a flashing check engine light.
The compressor circulates refrigerant through the A/C system and does most of the work of cooling the cabin. Warm air, odd noises or a clutch that will not engage are common signs of trouble.
A technician checks the system for leaks, removes what is left of the old refrigerant and refills it to the exact amount your car needs. Topping up without finding a leak only buys a little time.
This filter cleans the air that blows through your vents and traps dust, pollen and debris. Weak airflow or a musty smell often means it is overdue for a change.
Shocks and struts control how your car bounces over bumps and keep the tires planted on the road. A bouncy ride, nose dive when braking or uneven tire wear suggests they are worn.
Ball joints connect the wheels to the suspension and let them move up, down and side to side. Clunks over bumps or loose steering are reasons to get them checked before they wear further.
Wheel bearings let each wheel spin smoothly with very little friction. A humming or growling noise that changes as you turn is the classic sign that one is wearing out.
Fresh oil lubricates and cools the engine, and old oil gradually loses its ability to do both. Follow the interval in your owner's manual, and shorten it if you drive mostly short trips or in heavy traffic.
The tire pressure monitoring system warns you when one or more tires are low. Check the pressure with a gauge when the tires are cold, and let us know if the light stays on after you add air.
Rotating moves the tires between positions so they wear evenly, and balancing fixes small weight differences that cause vibration. Doing both on schedule helps your tires last longer and your ride stay smooth.
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