I have been using a LG G2x for the last 3 months or so. I have rooted the phone and have been using a custom rom for the last 2 months.

Yesterday the display on the phone stopped working. It will respond to the touch but I can't see anything.

I called T-mobile yesterday and they are sending me a replacement.

The problem that I am having is that I can't see the display so I can't flash my stock backup rom.

If I send the phone to them will they be able to see that I have flashed a custom rom to the phone? Will they even check for this?

The person I spoke with at T-mobile said as long as there is not any physical damage or the water damage indicator is white they will replace the phone.

I don't want to send my phone back to them and they find the phone has been modified and charge me full price for the new phone...