Cars are tough to troubleshoot! If you have the manual - sometimes you can find if/then case scenarios. Unfortunately MML doesn't have any auto manuals (I double checked) but they do have a category specific page for vehicles (see link below). On the page there is a service scheduler to assist you with setting up a service. I've noticed a lot of service special offers - so perhaps you can get a deal.
I once brought my car into a shop because my "check engine" light was on and the mechanic told me a quick rule of thumb:
A) If the light is orange/yellow - no rush - but you should think about scheduling an apt to bring your vehicle into the shop.
B) If the light is red - you should bring your vehicle in immediately.