How do I reset the check engine light on the 2001 Echo?

Resetting the check engine light on a 2001 Echo would require using an OBD-II reader to perform the reset. This is the surest way to actually clear it out. If You do not have access to one of those, You can try disconnecting the battery terminals of Your car and letting it sit for about ten minutes. This might reset the light, but will not always work. Please remember that clearing Your check engine light does not mean it will not return. If the underlying reason it came on is not taken care of, then it will come back on after a few miles of driving it. In some cases, it is just a routine reminder to service Your car with an oil change, so try that too.