Chapter 2 Basic Troubleshooting; Power On; Power Cords And Switches - NCR PC4i Service Manual

BASIC TROUBLESHOOTING
o 8237A DMA controller
o 8253 Timer
o 8259A Programmable Interrupt Controller
o Keyboard Interface
POKER ON

Power Cords and Switches

1. Ensure that the power cord is plugged into the
back of the computer
2. Ensure that the power cord is plugged into a
properly grounded wall outlet. (Use a lamp that
you know is in working order, and check that the
outlet has power.)
3. Ensure that the power cords for any currently-
attached external devices (printer, etc.) that
have separate
properly grounded wall outlets.
4. Insert the Service Diagnostic diskette into drive
A. Use a working copy of the original diskette.
Make a back-up copy on another computer,
necessary, but do not use a diskette that has no
backup. The possibility exists that a problem
could result in the loss of the software.
5. Turn ON any attached external devices that have
separate power cords and switches (unless the
device installation instructions specified that
the device be turned on after the computer).
6. Turn ON the computer power.
control and brightness to maximum.
2-2
STEP ONE
power cords are plugged
Turn the volume
into
if