Dell 2135cn Service Manual page 548

Chapter 3 Removal and Replacement Procedures (RRPs)
13) Remove the eight screws (silver, with
flange, 6mm) that fix the PWBA CONT AIO
to the printer.
14) Remove the one screw (silver, 6mm)
that fixes the USB connector of the PWBA
CONT AIO to the printer.
15) Remove the PWBA CONT AIO from
the printer.
3 - 46
Version 1 2008.02.01