Q: i phone 5s

Hello qualisfree,

Welcome to Apple Support Communities. It's my understanding you're unable to use the microphone on your iPhone with the Maps app.  I want to make sure your iPhone is able to detect your voice in all appropriate apps.

It's important to first test your microphones on your iPhone using images and steps in the link below:

Get help with the microphones on your iPhone, iPad, and iPod touch

If you continue to have issues try the steps in the "Get help" section of the link above.

Have a wonderful day!
 

Thank you for following up. At this point we'll need to back up and restore through iTunes. This will allow iTunes to remove all content and the software. It will then install a fresh updated software version. This process does erase all information and settings on your phone so it is extremely important you back up prior to restoring. The link below provides instructions on backing up and restoring with iTunes:

Use iTunes on your Mac or PC to restore your iPhone, iPad, or iPod to factory settings

Cheers.