most chain autoparts stores offer free trouble code service, such as autozone or advance auto parts, if your looking for a complete diagnostic, your probably gonna have to pay since the equipment to do so is quite expensive
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Most automotive parts stores will run a diagnostic check, free or charge.
Go to AutoZone. They do it for free.
Free if you go to the right mechanic
Auto Zone will check your computer codes for FREE...
You will need an OBDII scanner to retrieve the codes. WalMart has some for about $70 if you want to buy one. Otherwise, you can go to AutoZone and have it scanned free.
There are literally hundreds of diagnostic codes that would cause the check engine light to come on. Many auto parts stores will check the codes for free and tell you what is needed to fix it.
Sometimes you can connect the diagnostic tool and it will reset the check engine light. You can have Auto Zone or Advanced Auto connect the diagnostic tool for free.
free, head to advance auto parts or auto zone
try autozone.com has online manuals that give step by step how to
When the Check Engine Light (CEL) comes on, it means something wrong was detected, either with emissions or performance. When this happens, the computer will have a diagnostic code in memory that can be retrieved with an OBDII scanner. Auto Zone will scan and retrieve the diagnostic codes free of charge.
Diagnostic codes are generated by your on-board computer. They tell you what problems the computer has identified with your engine. The codes are numbers. The code numbers are read by an instrument that plugs into a special jack under the dash. Auto parts stores often will check your diagnostic codes for free, or you can have your dealer do it.