Service manual

Running the Dell Diagnostics: Dell Latitude CP
Why Run a Parallel Ports Test?
If the diagnostics does not recognize the computer's parallel port, check the Parallel Mode
option in the System Setup program to see if the port has been disabled. For instructions, see "
Parallel Mode". The subtests in the Parallel Ports test group cannot test a port unless it is
enabled.
When a port is faulty, it may not be immediately evident that the port, and not the device
connected to the port, is faulty. Instead, the peripheral (such as a printer) might behave
erratically or not operate at all. Also, if the external device is not properly installed through
software, it may not function properly. Try operating the peripheral from different programs or
through the operating system. If it still does not work, you can eliminate the software setup as
the cause of the problem.
Another possible cause for errors is a problem with the external device itself. Use the
documentation that came with the peripheral to troubleshoot it and confirm that it is working
properly. (Most printers have a self-test.)
After you eliminate incorrect system configuration information settings, peripheral malfunctions,
and software errors as potential causes of port problems, you can run the subtests in the
Parallel Ports test group to check your hardware. Although the following symptoms can be
caused by faulty peripherals or software errors, they might also suggest a port problem:
If a peripheral works intermittently or produces intermittent errors, the port may be faulty.
If the computer displays an error message that is related to the external device
connected to a port, but corrections to the device do not resolve the error, run the
appropriate subtest in the Parallel Ports test group.
If your software and the diagnostics do not recognize that you have a parallel port, you
should check the Parallel Mode system setup option, and if necessary, run the
appropriate subtest in the Parallel Ports test group.
Subtests
The four subtests in the Parallel Ports test group confirm the following port functions:
Parallel Internal Test
Checks several internal functions of the parallel port
Parallel External Loopback Test
Tests the functionality of the control lines through an external loopback connector, if an
file:///I|/SERVICE%20MANUALS/DELL%20MANU...ES%20REF%20AND%20TROUBLESHOOTING/RUN.HTM (31 of 37)6/21/2004 1:38:45 AM