If you want to reset the "check engine" light you should first determine and correct the reason why the light came on in the first place. Most full service auto parts stores can help you with that at no cost.
Check out the realted link for some advice on how to reset the computer in your 2003 BMW 325I computer.
how do you reset computer on a 2003 ford explorer after oil changes
do you have to reset computer after changing battery in 2003 745li
go to autozone and have them hook it up to there computer and if you've already fixed the problem they can reset it.
With a scan tool.
2003 sunfire
With a scan tool, or unhook the battery for 5 minutes
That requires an engine scanner.
where is the fuel filter located on a 2003 Pontiac sunfire
it may be the responders chip in the black computer behind da fuses
To find pictures of wiring diagrams for the 2003 Pontiac Sunfire for free check the library. Check in the non-fiction area under automobile repair. Many libraries have repair manuals from various authors. Chilton is a more popular author of this type of manual.
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