Important Notice For Replacing A System Board; How To Use Error Codes; Strategy For Replacing Frus For Cto, Special-Bid, And Standard Models; Product Definition - Lenovo ThinkPad T490 Hardware Maintenance Manual

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).
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T490 Hardware Maintenance Manual