About This Manual - Lenovo ThinkPad Edge E420s Hardware Maintenance Manual

About this manual

This manual contains service and reference information for the following ThinkPad
ThinkPad Edge E420s and S420
Machine Type (MT) 4401
Use this manual along with the advanced diagnostic tests to troubleshoot problems.
Important:
This manual is intended only for trained service technicians who are familiar with ThinkPad products. Use
this manual along with the advanced diagnostic tests to troubleshoot problems effectively.
Before servicing a ThinkPad product, be sure to read all the information under Chapter 1 "Safety
information" on page 1 and Chapter 2 "Important service information" on page 27.
© Copyright Lenovo 2012
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