Where can I find the Hearing Test on AirPods Pro 2?

There are a several things to consider here. First, your iPhone must be on 18.1 not 18 to use the hearing aid function. Second, What is the firmware on your AirPod Pros 2? Next, this function is not available in all countries. Where are you located?

In order to use the hearing test and hearing aid function, three things must be true. 

1. Your iPhone must be updated to 18.1. Here are instructions to update. Update your iPhone or iPad - Apple Support
2. Your AirPd Pros 2 must be updated to their latest firmware, which 7B19. Here are instructions to update. About firmware updates for AirPods - Apple Support
3. You Apple Account must be registered in a country that supports the hearing aid feature. Check your country here.  AirPods Pro 2 - Hearing Health Feature Availability - Apple

Glad it worked out for you!

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