 If the headlights don't change, that means the starter's not doing anything. Why isn't it doing anything? Again, it could still be a starter. Does the starter have a good connection at the solenoid? Is it making all proper connections? So you can tell that. Now, if you want to get into this deeper, break out your scan tool. You know, it's funny what you can do with a scan tool. You don't necessarily think of using a scan tool, a diagnostic scan tool, as part of a no-crank diagnosis.