Agilent Technologies Infinium DCA 86100A Service Manual page 148

Replacing Instrument Assemblies
To Replace the Display Backlights
Figure 7-19. Removing the Backlight
N O T E Pay attention to the orientation of the backlight as you remove it, to ensure correct replacement.
5 Repeat steps 3 and 4 to remove the bottom backlight.
6 To re-install the backlights, perform the above steps in the reverse order.
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