So your Check Engine light is on, staring at you every day. You know there must be something wrong, but you don't want to pay to have the problem diagnosed. Don't worry - we've got you covered. With a simple code-reader tool, you can find out what's wrong and turn the light off.
When the Check Engine light is on, it means one or more trouble codes are stored in your vehicle's computer. Trouble codes tell you that a problem was identified in the engine-management system. Reading the stored trouble codes is the first step in diagnosing the problem.
Reading trouble codes is easy. Code readers are available for less than the cost of an hour's shop labor and can be used on any 1996 or later vehicle. Often, your local auto parts store will loan you a code reader or even read the code for you at no charge.
The code(s) will look cryptic until you use a Haynes manual to decode them. Be sure to write down each code, since you will be deleting them from your computer's memory. Basically, each code identifies a circuit in the electronic engine management system where a problem was found. For information on repairing these problems, get Haynes Manual #10206, OBD-II and Electronic Engine Management Systems.
Once you've recorded the codes, you can erase them. If you don't fix the problem that caused the code, you'll probably be annoyed by the Check Engine light again. But at least you now know how to read and erase the codes.
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