What does the check engine light of your Trailblazer EXT mean?

What does the check engine light of your Trailblazer EXT mean?

In a few words:
It’s a warning light that alerts the driver about any type of engine problems. In some vehicles, the light comes in two colors: yellow to indicate minor problems and red to indicate serious problems.

The check engine light is part of every vehicle that has an electronic engine management system, either an integral one or only for fuel ignition. Its function is to alert the driver about any type of engine problems.

While driving, the computer of your Trailblazer EXT (ECU o PCM) monitors air/fuel supply and exhaust gases in order to verify that the engine is working properly. If any problem is detected, the check engine Light of your dashboard will turn on.

Depending on the type of failure, the light may either blink or remain constantly lit. If the problem is serious, your Trailblazer EXT will be in a “emergency” state that will prevent you from accelerating the engine above certain speed limit, forcing you to drive at low speed in order to avoid further damages.

The check engine light can alert you about some failures but not all of them. It will depend on how complex the electronic control unit of your Trailblazer EXT is.

To properly diagnose the failure of your Trailblazer EXT, it is important to have a suitable scanner that is compatible with the brand and model of your car. The scanner will show the engine fault code that the computer has detected, which is related to a certain problem that is affecting the engine.

The most common check engine light causes of your Trailblazer EXT and how to detect them.

  • Ignition cylinder problems: irregular engine running.
  • Problem with exhaust gas oxygen sensor (Lambda probe): irregular engine running, there are misfires when accelerating abruptly or driving at low revs. It may be caused by a sensor fault or a failure of the catalytic converter.
  • Problems with the engine intake (air or fuel): engine running may be rough or irregular.
  • Problems with the electrical system: sometimes it is easy to identify the cause but other times it may take days of testing to find the source of the problem.
  • Sensor malfunction: It affects engine running or stops running completely.
  • Wiring problems: contact failure, cut wires, short circuits.

Indicator status and severity

The check engine light can behave in different ways. Here we show you the most common light signals so you can know what is happening to your Trailblazer EXT:

  • The light turns on when you switch on the ignition key and then it turns off: It’s normal. It’s used to verify that the light itself is working and the bulb is not burned out.
  • The light blinks and then it turns off (cyclically): This indicates that the car had a problem at one point but it is not happening at the moment.
  • The light is steady: This indicates that there is a problem but is not so serious as to stop driving your vehicle.
  • The light blinks continuously: This indicates that there is a critical problem. Usually, you should stop driving your vehicle.

Keep in mind that if you have a top-quality scanner, you will be able to verify all the car sensors, avoiding blind maintenance which is a pointless waste of money. Another recommendation is to check the owner's manual, if you want to know more about the fault codes that the scanner will detect.

Have you found an error in this guide? Let us know
Was this information useful?
Thank you!

Chevrolet Trailblazer EXT problems: The check engine light


Do you like StartMyCar? Follow us on Facebook


Did you find the website helpful?

Thank you!