So you had your oil changed or changed it yourself on you GM vehicle and the little light on the dashboard still says "Change Oil Soon". Your owner's manual should tell you how to reset it, however it's hidden away in one chapter or another.Here are the two easiest ways for most GMs.
First you need to turn your car On. This is not starting the car! Turn the key two "clicks" forward. All the dashboard lights should come on, along with the radio and odometer.
If your GM has the four buttons on the dashboard with all sorts of information:
One button should have a road or "i" on it. Pushing this button will show your mileage, tire pressure, operating temperature, and all sorts of other stuff.
You are looking for "oil life ##%". Once you find this, press and hold the button with the checkmark on it. After 5-10 seconds it should flash "oil life reset". Tada!
If your vehicle does not have the buttons mentioned above:
Turn the car "On" (without starting car!!)
Press the gas pedal all the way to the floor 3 times within 5 seconds. This is trickier than it sounds. It must be pressed ALL the way to the floor ALL 3 times.
Then wait 5-10 seconds. The Change Oil Soon light should blink then go out. If not, turn the car off and go through the steps again.
Read more: How to Reset Change Oil Light on GMs, Chevrolet | eHow.com http://www.ehow.com/how_4663244_change-oil-light-gms-chevrolet.html#ixzz1FkudcURK