Same happened to me. It would come on, then a few days later it would go off. Took it to Jiffy Lube for an oil change, and they came in and told me that the connector to the light was loose. So they pluged it back in. And its fine now. I believe Auto Zone does a free diagnostic test. You could do that to see if anything is wrong first. Hope that helps
How do I reset the service engine light on a 2003 Chevy Trailblazer?
can you tell me why my 1999-2000 Chevy trailblazer light is on
When service engine light is on on a 2003 Chevy Trailblazer, the problem could be a faulty thermostat, a circuit range performance problem, or any other problem.
With a code reader. Have your local auto parts store read the code(s). They provide this service for free.
The "Reduced Engine" Warning Light alerts drivers when/if there is a serious problem with the transmission and/or one or more of the engine system components.
In US it says "SERVICE ENGINE SOON" in Canada it looks like an engine.
Maybe you should service the engine soon. :P
how do you replace side marker light on 2008 chevy trailblazer
There are pages and pages of things that can cause a check engine light. You need to have it checked with a scantool. Then the code can be diagnosed and repaired.
Check
The symbol of a wrench and an oil can on the dash of a Chevy Trailblazer means that your vehicle needs oil. If the light doesn't go away oil is added, you need to take your vehicle in for service.
Get the Trouble code read then have it reset at the same time. You can also disconnect the negative battery terminal for 10 minutes and it will reset. If you have not fixed the problem the code will set again causing your check engine light to come back on.