How to Reset the Check Engine Light on a 2003 Trailblazer
- 1). Turn the ignition key to the "II" position.
- 2). Open the hood of the car, then open the fuse panel cover located in the engine bay. The fuse cover is held in place with retaining clips, so you'll need to pull up on the cover quite hard to pull it off. Then, pull the PCM BAT and PCM IGN fuses from the fuse panel. Use the fuse diagram on the underside of the cover to locate these fuses.
- 3). Wait five minutes and then turn the ignition key to the "off" position.
- 4). Place the fuses back into the fuse panel, in their proper location.
- 5). Start your Trailblazer to verify that the check engine light went off.
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