Multi touch screen grounding issue


New member
Nov 12, 2018
Hi all,

I have a problem with my phone. When I put it on a material that has good electrical insulating properties, for example on a couch and try to use two or more fingers, e.g. zooming in - zooming out on a picture, the touch sensing of the screen blocks and becomes not responsive. One finger is always sensed but 2 or more fingers are sensed only for a short time or not at all. The more fingers you put on the screen the easier is to make it stop sensing your fingers.

This behaviour is more obvious when you repeatedly move your fingers inward till they touch and outward again.

When multi touch sensing blocks, one way to make it work again is to touch with one finger of your other hand the hull of the phone, e.g. the charging socket of the phone, making in this way a kind of grounding.

For visual demonstration you can use a multi touch sensing app, such as MultiTouch or other similar one.

The problem never occurs when:
- phone is handheld
- it is charging
- it is lying upon a not so good insulator, e.g. on a wood or a whasing machine.

I have made some videos that illustrate the problem:

The strange thing is that I sent my phone to Nokia for repair and they exchanged my phone with a new one which however exhibits the same problematic behavior. This led me to think that many of Nokia 7 plus may suffer from this problem.

Could anyone else please confirm that he/she has the same problem with their phone or not?