my 01 civic lx has a cel and i have my own scanner but when i plug it in nothing happens. it should light right up and start reading, but i get nothing. is there a fuse or something that i dont know about? i thought it was connected directly to the ecu.

 

Check fuse 9 in the under-hood fuse relay/box (see picture). Note that multiple other functions would also be lost if fuse 9 were blown.

 

fuse no9 is good i think i may have lost the ground, anyone have any idea where to find that?

 

The manual for your code reader may show a diagram of the data link connector (DLC), where you can determine which terminal supplies battery power. With this information, you can use a multimeter or test light to directly test whether your car's DLC is receiving battery power. If so, the problem might be your code reader.

 

See picture. Again, it may be helpful that the same ground is shared by several other components.

 

my code reader is good i just used it on my wifes car to check it. as for shared grounds my car is m/t and have no heated seats. i did have my center console out today installing a new shifter boot, i may have knocked something loose, but i dont think i did.

 

Edit: Comment deleted - your previous post answered the questions.