No SES light but codes show on a scan tool
* toggle whether or not the SES light is enabled
* toggle the MIL (malfunction indictor lamp) error mode:
** MIL set on first error
** MIL set on second error
** No MIL light
** No error reported
So I'd bet the SES is disabled in the tune but it is still set to generate a MIL. A scan tool will see the codes even if the SES indicator is not lit in this scenario.







