The icon will appear as a set of grey gears located on the Home Screen.;
, It is located in the fifth set of menu options.
 This button is located in the Preferred Transportation Type section. A blue check mark will appear next to the button, indicating that Maps will now automatically look up transit routes anytime you search for routes to a particular destination.In order to select what types of routes Maps searches for, tap on the second Transit button in the second set of menu options. From here, tap on each mode of transit you want to include or remove from the Maps search results. A blue check mark next to a transit option indicates that mode will be included in the search results.
Open your iPhone’s Settings.
Scroll down and tap Maps.
Select the first Transit button.
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