OK I have a 2002 trans am and the check engine light didn't work when I bought it from a friend so I changed the cluster and that fixed the problem. A few weeks later the light just quit coming on again (when I first turn the key on) also I have a bad o2 sensor so I know the light should stay on but it dosnt even come on when I cycle the key on. If anyone has had this problem before please chime in. Thanks