Connect AC adapter and retest Multi-Touch.
Connect the user’s iPad to a USB power adapter and retest Multi-Touch.
If the user brought along the USB power adapter that came with his/her iPad, use that adapter. Otherwise, use a known-good USB power adapter of the same type and wattage as the one that shipped with the user’s iPad. For example, for most iPad models you should use the Apple 12W USB Power Adapter.
Retest by launching the Maps app and performing the following tests:
Double-tap each corner of the map, then the center to verify that it zooms in everywhere you tap.
If a specific area is affected in another app, note location, and verify touch functionality for that location in the Maps app.
Be sure to test the device in all rotated orientations.