check engine light on but goes out when you turn on the lights

Did you ever figure it out?

Everybody would have Ford Taurus check engine light on no codes goes out when you turn the headlights on move the rheostat up and down with headlights on if the light gets dimmer and brighter pull the instrument cluster carefully and look at the copper contacts looking at the back of the speedometer you'll notice the two contacts one moved the second from the right on the right contact in the printed circuit moved and is underneath the other finger and causing an unintentional circuit it has to be moved back over and glued in place somehow or a new circuit board which probably isn't going to happen but that's the facts and that's what's wrong with your

This is Wolf one alpha one. I found the fix for the check engine light on the Tarsus when you turn the lights on it goes out there's no codes there is some typos in my previous explanation if you can forgo that and you're intelligent enough to do this work you should be able to read between the lines I hope it helps a lot of people and they good luck following take care

We are having the same problem with our 2003 ford Taurus. Check engine light, seatbelt light and door ajar light are on. NO CODES were shown and cant clear codes that are not there. Weve grease up all connectors and nothing worked. Replaced body control module, light switch for the head lights. We're not checking the copper wires, some a re e touching. Fingers crossed.

Well we took the dash out and check all copper wires and there was some touching fixed that and now CHECK ENGINE LIGHT IS OFF. YEAH!!!!!

Is this the board you are refering to? Back of the speedometer?

Found it