IBM ThinkPad 770E, Hardware Maintenance Manual

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CHECKOUT GUIDE
Modem (DSP) Checkout
Note
This section is for the built-in modem model.
Do the following:
1. Go to the diagnostic menu by selecting Test in the
Easy-Setup menu.
2. Select DSP and run the diagnostic tests.
3. If the test detects a DSP problem, replace the modem
card.
Port Replicator Checkout
Use the following procedure to isolate a port replicator
problem. The port replicator attaches to the system
expansion connector at the rear of the computer:
1. Power off the computer.
2. Remove the failing devices from the port replicator.
3. Unplug the AC Adapter from the port replicator, if
attached.
4. Remove the port replicator from the computer.
5. Reconnect the failing device directly to the computer.
(If another device is already connected to the
computer, remove it first.)
6. Go to the “Running the Diagnostics” on page 40 and
run the diagnostics.
7. If the advanced diagnostic device test did not find an
error, suspect a problem with the port replicator.
8. Power off the computer and reconnect the port
replicator.
9. Power on the computer and run the following
advanced diagnostic tests:
Ÿ
Serial port test with the wrap plug installed on
the port replicator
Ÿ
Universal serial bus test with the USB parallel
test cable
Ÿ
Parallel port test with the wrap plug installed on
the port replicator
Ÿ
FDD-2 device test on the failing device with a
scratch diskette
10. If diagnostic errors appear, replace the port replicator
or the diskette drive. If the problem remains after the
replacement, replace the system board.
11. If power problems appear only when the port
replicator is used, replace the port replicator.
Port Replicator Power Overload:
If power
shutdown occurs intermittently when PC Card devices are
used through a port replicator with PC Card slots, suspect
an over-current problem. Some PC Card devices use
more power; if the maximum usage of each device occurs
simultaneously, the total current will exceed the limit,
thereby causing a power shutdown. Isolate this problem
General Descriptions
35