Important notice for replacing a system board, How to use error codes, Product definition – Lenovo ThinkPad E555 User Manual
Page 32: Fru identification
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Attention: The drive startup sequence in the computer you are servicing might 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.
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 Ball Grid Array (BGA) chipset.
How to use error codes
Use the error codes displayed on the screen to diagnose failures. If more than one error code is displayed,
begin the diagnosis with the first error code. Whatever causes the first error code might also cause false
error codes. If no error code is displayed, see whether the error symptom is listed in the “Symptom-to-FRU
Index” section.
Strategy for replacing FRUs for CTO, special-bid, and standard models
This topic provides information about the model types and FRU identification.
Product definition
This topic introduces different model types and how to identify each type.
Dynamic Configure To Order (CTO) model
This model provides the ability for a customer to configure a Lenovo solution from a Web site, and have this
configuration sent to fulfillment, where it is built and shipped directly to the customer. The machine label and
eSupport will load these products as the 4-character MT, 4-character model, and 2-character country code.
The model is “CTO1” and the default country code is “WW” (example: 20AACTO1WW).
Special-bid model
This model is a unique configuration that has been negotiated between Lenovo and the customer. A unique
MTM consists of a 4-character MT, a 4-character model, and a numeric 2-character country code is provided
to the customer to place orders (example: 20AA000955). The country code assigned is numeric and does
not designate a specific country or region. The custom model factsheet for the MTM indicates which country
the special-bid MTM is set up for. Special-bid offering is not generally announced.
Standard model
Standard models (fixed configuration) are announced and offered to all customers. The MTM portion of the
machine label consists of a 4-character MT, a 4-character model, and an alphabetic 2-character country
code. The country code assigned is alphabetic and represents a designated country or region (example:
20AA0009UK).
FRU identification
Use Lenovo eSupport to identify major FRUs, FRU part numbers, and FRU descriptions for a product at an
MT - serial number level. Examples of major FRUs are hard disk drive, system board, liquid crystal display
(LCD), and memory module.
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Hardware Maintenance Manual