About This Manual - Lenovo ThinkPad L420 Hardware Maintenance Manual

About this manual

This manual contains service and reference information for the following ThinkPad
ThinkPad L420
Machine Type (MT) 7826, 7827, 7829, 7853, 7854, and 7856
ThinkPad L421
MT 7826, 7827, 7829, 7853, 7854, and 7856
ThinkPad L520
MT 5015, 5016, 5017, 5019, 7859, and 7860
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 25.
© Copyright Lenovo 2011
®
Notebook products.
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