Lenovo ThinkPad X390, Hardware Maintenance Manual, Page: 27 / 108

Chapter 2. Important service information
This chapter introduces following important service information that applies to all machine types supported
by this manual:
• “Strategy for replacing FRUs” on page 21
– “Strategy for replacing a storage drive” on page 21
– “Important notice for replacing a system board” on page 22
– “How to use error message” on page 22
• “Strategy for replacing FRUs for CTO, special bid model, and standard models” on page 22
– “Product definition” on page 22
– “FRU identification” on page 22
Important:
• Advise customers to contact the Lenovo
®
Customer Support Center if they need any assistance in
obtaining or installing any software fixes, drivers, and UEFI BIOS downloads. Telephone numbers for
Lenovo Support are available at:
https://pcsupport.lenovo.com/supportphonelist
• System Disassembly/Reassembly videos that show the FRU removals or replacements for the Lenovo-
authorized service technicians are available in the following support site:
https://www.lenovoservicetraining.com/ion/
Strategy for replacing FRUs
Before replacing parts:
Ensure that all software fixes, drivers, and UEFI BIOS downloads are installed before replacing any FRUs
listed in this manual.
After a system board is replaced, ensure that the latest UEFI BIOS is loaded to the system board before
completing the service action.
To download software fixes, drivers, and UEFI BIOS, go to https://support.lenovo.com and follow the
instructions on the screen.
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.
Strategy for replacing a storage drive
Always try to run a low-level format before replacing a storage drive. This will cause all customer data on the
drive to be lost. Be sure that the customer has a current backup of the data before doing this task.
Attention: The drive startup sequence in the computer you are servicing may have been changed. Be
extremely careful during write operations such as copying, saving, or formatting. If you select an incorrect
drive, data or programs can be overwritten.
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