About this manual
This manual contains service and reference information for
IBM ThinkPad T20, T21, T22, T23 (MT2647, 2648), and
ThinkPad Dock (MT2631) products. Use this manual along
with the advanced diagnostic tests to troubleshoot
problems.
The manual is divided into sections as follows:
v The common sections provide general information,
guidelines, and safety information required in servicing
computers.
v The product-specific section includes service, reference,
and product-specific parts information.
Important
This manual is intended for trained service
personnel who are familiar with ThinkPad products.
Use this manual along with the advanced diagnostic
tests to troubleshoot problems effectively.
Before servicing an IBM ThinkPad product, be sure
to review the safety information under “Safety
notices: multilingual translations” on page 3, “Safety
information” on page 13, and “Laser compliance
statement” on page 18.
© Copyright IBM Corp. 2002 iii