Because there is two sets of connectors under steering colum (black and green) disconnect both of these (just pull apart the black ones then the green)these as diagonostics connectors.if you have a error in ecu check engine will flash with a code e.g slow then fast.slow is tens fast is one.slow,slow,fast,fast,fast code23.if you have a prolem get it fixed.if there is no error check engine will flash on off on off continusly when these connectors are together.