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What Does the "Check Engine" Light Mean?

What Does the 'Check Engine' Light Mean?

Have you ever pulled out of your driveway and glanced down at the speedometer only to notice the words “check engine” brightly lit? Engine problems can be very serious. But what exactly does that light mean?

Know What to Look for

Every car is different. Some vehicles have one check engine light to cover a variety of issues, while others have both yellow lights to indicate a maintenance issue and red lights to indicate an urgent problem. When you see the light, there are a few things experienced mechanics recommend:

  • Note the color of the check engine light.
  • Consider yellow as a caution indicator.
  • Consider red as a critical warning.
  • Consult your car owner manual to learn if you have red and yellow indicator lights or single-color.
  • If you only have a single-color warning light, consult your mechanic right away.

Regardless of your warning system, there are varieties of things that can cause it to light up:

  • Low oil
  • Low transmission fluid
  • Low brake fluid
  • Low anti-freeze

The lights can also indicate serious problems, including:

  • Broken belts
  • Faulty sensors (your car uses these to regulate combustion and other processes)
  • Bad catalytic converter (used to control emissions)
  • Anti-lock brake problems
  • Airbag issues

Take Action

What should you do when your check engine light comes on? A mechanic should address red-light problems right away. A yellow light is a warning, but depending on the vehicle, you might have a small amount of time before that yellow light turns into a red light.

The bottom line? Take your car to be serviced as soon the check engine light comes on. Do not delay! If you let the problem go, you risk damaging your vehicle because:

  • Your car may have an oil leak.
  • The car may have faulty brakes that don't work when you need them.
  • You could have a broken alternator belt (part of the system which keeps your battery from dying).
  • The car could fail due to a bad fuel sensor.

Garage mechanics typically connect a device to the car’s computer to read the problem and diagnose the car trouble. This quick and easy method often gives the mechanic enough information to make an educated guess on repair costs.

Do not be alarmed if your check engine light comes on briefly and then goes away a few seconds later after starting your car. That is normal. Only be wary when the light comes on and stays on.

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