Checking Engine Codes

How and where in the car do you plug everything in to check the codes that are stored in the engine computer? I was out running errands today and halfway through the check engine light came on. So I would like to know how to find out what the code means so that the problem can be fixed.

check here http://www.automotiveforums.com/vbulletin/showthread.php?t=908874 I think you'll find all the information you need.

So I'm still a little confused all I have to do is remove and then replace the fuse under the dash. Then I read the codes and look in the shop manual to find out what it means. I thought that I had to use a multimeter to check the codes.

Alright so I went out today when it was cool enough to check the codes. The code that was flashing is 23. What does this code mean? When I searched in the manual all I could find was a section for an automatic which my car is not. Can you use the same codes for both manual and automatic or do they come out with different results?

Code 23 is intake air temperature sensor. I think on a three cylinder it is a black plastic thingy that plugs into the UFO shaped section of the air cleaner assembly. Probably disconnected.

Thank you to everyone that helped me on this. I go the piece plugged back in and now when I checked I flash a 12, which menas I'm good to go.

Also that black plastic piece that has two wires coming from it and connects to the back of the air filter sometimes has a gasket on it. I think that my problem was that, that gasket was blocking the sensor inside from making a full contact so I took it off. And now I have no problem at all.