Factory Test Items; Strategy For Replacing Frus; Important Notice For Replacing A System Board - Lenovo ThinkPad 13 Hardware Maintenance Manual

10. After the repair process finishes, the battery is disabled. The system is in a clean out-of-box state. In
order to turn on the computer, attach the Lenovo USB-C 45W AC Adapter to the computer first. If
applicable, customers must re-enroll the system for enterprise enrollment.

Factory test items

After the system enters the factory-test-image environment, factory test items will run. The factory test
process contains the following three types of tests:
• FATP Test: The FATP Test is designed to test the individual component to verify its function, such as
the TPM, display, audio, camera, keyboard, and other components. It is recommended that you run all
the FATP Test items. Some test items might require an HDMI monitor or an SD card. If the devices are
not available, the tests can be bypassed, but with the overall test marked as failed. This will require the
finalized step of the GoogleRequiredTests to be forced in order to complete the servicing of the computer
(see step 9 in "Using the repair shim" on page 23).
• Stress Test: The Stress Test is designed to test how the system functions under stress by running the
maximum workload applications. The Stress Test includes the test of memory, microprocessor, and
graphics card. The test takes about 10 minutes to finish.
• GoogleRequiredTests: GoogleRequiredTests checks the system status and helps reset the system back
to the factory-default settings. If any test fails, the system cannot be finalized. The following items are
some common mistakes that lead to GoogleRequiredTests failure:
– HWID mismatch: Each Chromebook has a known hardware configuration. Each configuration is
assigned an HWID. HWID mismatch can be caused by using unauthorized parts, or missing parts.
For information about HWID, see "Hardware identity" on page 46.
If the write-protect function is not turned off before recovering the computer with the repair shim, it
will also cause HWID mismatch. For instructions on how to turn off the write-protect function, see
"Removing and reinstalling the write-protect screw" on page 22.
– Write-protect function is off: System cannot be finalized until the write-protect function is turned
back on.

Strategy for replacing FRUs

Use the following strategy to prevent unnecessary expense for replacing and servicing FRUs:
• If you are instructed to replace a FRU but the replacement does not correct the problem, reinstall the
original FRU before you continue.
• Some computers have both a processor board and a system board. If you are instructed to replace either
the processor board or the system board, and replacing one of them does not correct the problem,
reinstall that board, and then replace the other one.
• If an adapter or a device consists of more than one FRU, any of the FRUs may be the cause of the error.
Before replacing the adapter or device, remove the FRUs, one by one, to see if the symptoms change.
Replace only the FRU that changed the symptoms.

Important notice for replacing a system board

Some components mounted on a system board are very sensitive. Improper handling of a system board can
cause damage to those components, and may cause a system malfunction.
Attention: When handling a system board:
• Do not drop a system board or apply any excessive force to it.
• Avoid rough handling of any kind.
• Avoid bending a system board and hard pushing to prevent cracking at each BGA (Ball Grid Array) chipset.
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ThinkPad 13 Hardware Maintenance Manual