Chevrolet trailblazer problems engine light - 2007 Chevrolet TrailBlazer SS

First you need to have EBCM - electronic brake control module check for DTC'S - diagnostic trouble code's . If the light is on there is a code stored . I think most part stores can do this and for free . After you find out what code is stored , looking up that code in service repair information for diagnostic trouble shooting chart would be next step . There are a few codes too.
DTC C0035 or C0040
DTC C0045 or C0050
DTC C0110
DTC C0131
DTC C0161
DTC C0186
DTC C0196
DTC C0201
DTC C0240
DTC C0241 or P0856
DTC C0244 or P1689
DTC C0245
DTC C0283
DTC C0287
DTC C0290 or C0292
DTC C0455
DTC C0550
DTC C0558

Find the code do the diagnostic's , fix the problem , wiring issue's , a sensor , bad module ,what ever it is . The light will go out then . Here is a sample of code discription .
• DTC C0035 Left Front Wheel Speed Sensor Circuit
• DTC C0040 Right Front Wheel Speed Sensor Circuit

No, the check engine light will not reset unless cleared with a scan tool or after a lot of key cycles with the problem resolved. You need to get it scanned to see what the code in the system and have it repaired. Most autozones will scan your codes for free - but they just give you the code and their guess of whats wrong with it.

If the service engine soon light is flashing, it means the computer has detected an engine misfire with the potential of catalytic convertor failure. Don't just tune it up. Bring it somewhere they can read the trouble code. Sometimes it will designate which cylinder is having the problem.

You will need a code reader to clear the service engine soon light. If you have not repaired the problem the light will come back on.

You'll need to read the engine code first thing.

Is the Check Engine light on? If it is, you need to have the codes read to determine the cause. The code(s) will point to the area of the problem. This could be a bad spark plug, bad ignition coil, bad injector, etc.

The service engine light comes on when the computer determines there is problem. You need to have the fault codes scanned when the light comes on.

More than likly its an ignition swich. Very common problem. The quick way to check it; when it is acting up take a test light and put it on one of the engine fuses in the underhood box. If it's half lite then you have a power feed problem which is most always the ign switch.

is this the check engine yellow light?

the check engine? you need to have it scanned and the codes cleared at an autoshop. it will just pop back on if the problem isnt taken care of.