When an application such as Maps uses the Location Services on iPad it will prompt a warning. When you are tapping OK twice on the warning from the same app the warning will no longer show. You can reset the Location Warning so that it would prompt again. Here's how:
1. Go to the Home Screen.
2. Tap on Settings.
3. Tap on General.
4. Tap on Reset.
5. Now select Reset Location Warnings.
You may be ask to enter a passcode, when prompt put in your passcode.