There is one way of turning off the check engine light using a OBD II Scan Tool but it won't help passing the smog check without taking a risk because it will also erase the emission monitors, and that will cause a smog test failure. The "emission monitors" are internal self-tests which the Engine Control Computer uses to identify whether a particular emission system is functioning properly.
Without the required monitors complete your T-Bird can't pass the smog test.
You can use a scan tool to erase the stored trouble codes (which indicate where the emission fault is), which will turn off the service engine soon light and delete the completed monitors (all of which we do not recommend). You will then need to drive your Ford for 1 to 2 weeks to complete the monitors again while hoping the Service Engine Soon light will not turn on again, and somewhere in between try to get a smog check and pass it.
Our recommendation would be to seek repairs and solve the smog check problem once in for all.
posted by SmogTips Support 11-16-2011 04:14 PM