Important Notice For Replacing A System Board; How To Use Error Codes; Strategy For Replacing Frus For Cto, Cmv, And Gav; Product Definition - Lenovo ThinkPad T520 Hardware Maintenance Manual

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.
Note: If your computer is shipped with an mSATA drive and a solid state drive or hard disk drive, the mSATA
drive will be seen as hard disk 0 in the system, and assigned drive C:. The solid state drive or hard disk drive
will be seen as hard disk 1, and assigned drive D:. The mSATA drive is installed in the wireless WAN card slot
of the computer. The Lenovo preloaded software is installed on the mSATA drive.

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.

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 may also cause false error
codes. If no error code is displayed, see whether the error symptom is listed in the Symptom-to-FRU
Index for the computer you are servicing.

Strategy for replacing FRUs for CTO, CMV, and GAV

Product definition

Dynamic Configure To Order (CTO)
This provides the ability for a customer to configure a Lenovo solution from an eSite, and have this
configuration sent to fulfillment, where it is built and shipped directly to the customer. The machine label,
Product Entitlement Warehouse (PEW), eSupport, and the Hardware Maintenance Manual will load these
products as the 4-digit MT and 3-digit model, where model = "CTO" (example: 1829-CTO).
Custom Model Variant (CMV)
This is a unique configuration that has been negotiated between Lenovo and the customer. A unique 4-digit
MT and 3-digit model is provided to the customer to place orders (example: 1829-W15). A CMV is a special
bid offering. Therefore, it is not generally announced.
• The MTM portion of the machine label is the 4-digit MT and 3-digit model, where model = "CTO"
(example: 1829-CTO). The PRODUCT ID portion of the machine label is the 4-digit MT and 3-digit CMV
model (example: 1829-W15).
• The PEW record is the 4-digit MT and 3-digit model, where model = "CTO" (example: 1829-CTO).
• eSupport will show both the CTO and CMV machine type models (example: 1829-CTO and 1829-W15 will
be found on the eSupport site.)
• The Hardware Maintenance Manual will have the 4-digit MT and 3-digit CTO model only (example:
1829-CTO). Again, CMVs are custom models and are not included in the Hardware Maintenance Manual.
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Hardware Maintenance Manual