Hi my name is John.
You disconnect the postive battery and wait 10 min,than hook up the postive cable and turn the key on.
Let me know if you need more.
Please push the accept button when were done.
Thank you for choosing just naswer.
Did the light come back on because there is still a problem.
That how you reset the main computer.
If the gas cap was off it will set a code.
the code will go away after you start an drive the car like some where between 3-40 times on it own if that all is wrong.
This should have clear that code.