I have a 2008 corolla. It has an auto light when the car needs an oil change. I need to know how to reset it.

Note -- DO NOT depress brake pedal when selecting modes to avoid engine from starting.
On vehicles with Smart Key system, make sure smart key is in the vehicle. Pressing the Engine Start Stop switch changes the ignition switch mode as follows.
First Time -- ACC mode -- accessories on.
Second Time -- On mode, power on and all accessories on.
Third Time -- Power Off Mode, indicator light is off.
To reset Maintenance Reminder Light after engine oil replacement, place Smart Key system in power off mode with odometer reading showing. Place Smart Key system On Mode while holding down trip meter Reset button.
Hold trip meter Reset button down for at least 5 seconds. A Odometer should indicate "000000"
This procedure is for car without Smart Key system.
To reset Maintenance reminder light after engine oil replacement, turn ignition switch to off position with odometer reading showing. Turn ignition switch to on position while holding down trip meter reset button.
Hold trip meter reset button down for at least 5 seconds. A odometer should indicate "000000" and Maintenance reminder light goes out.
and Maintenance reminder light goes out.

Here's how you reset your oil maintenance light.

To reset the light,
Turn the ignition on
Make sure the odometer displays "ODO"
1.Turn the key off
2.Press and hold down the same button you use to get to "ODO"
3.Turn the key back to ON ( while still holding down the button)
4.Hold the button in until all the flashing lines on the odometer go away and the bunch of "000000" shows up and the maint reset light will turn off.
Your'e done.

If this doesn't work, you would have to try it on "trip A" instead of "ODO".

Look in your owners manual and go to the part that explains the different symbols on your dash. Look for that service reminder and it should tell you what page to go to to learn more about that. Somewhere there should be some wording to the effect that "When you have your car serviced by a certified Toyota dealer they will reset it for you. In the event that someone other does your maintenance then this is the procedure to reset......."