How to adjust the brightness display on an iSC250

Summary:

How do I change the brightness on the Ingenico iSC250?

Solution:

Hold Clear and <minus> until the device reboots.
During startup, on the gray Retail Base App info screen select: 2, 6, 3, 4, then <Enter>
Then <+> to get the menu
Select Telium Manager
Initialization
Hardware
Display
Back Light, move the slider to adjust to desired brightness.