Clearing the Codes

Is there any way to completely clear the codes on the computer? The reason I ask is, I had it in the shop last week and the tech said he checked for codes and it threw none. However the CEL came on AGAIN yesterday. I wonder if it can hold old codes that have since been fixed.
Thanks!

Autozone will check and clear any codes for you for free.

Or you can just erase the codes by pulling the ECM fuse in the engine compartment fuse box for a few seconds. It will clear the codes but if it comes back on i would go to autozone and have them check the codes to see what is going on.

Good Luck

yup it will hold old codes for about 30 restarts. To reset the codes you can also disconnect the battery for 15 mins