Lenovo ThinkPad T420 Support Question
Lenovo ThinkPad T420 Support Question
Find answers below for this question about Lenovo ThinkPad T420.Need a Lenovo ThinkPad T420 manual? We have 38 online manuals for this item!
Question posted by TswhZa on February 20th, 2014
Thinkpad T420 Cannot Adjust Brightness
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Related Lenovo ThinkPad T420 Manual Pages
Hardware Maintenance Manual - Page 1
ThinkPad T420 and T420i Hardware Maintenance Manual
Hardware Maintenance Manual - Page 3
... symptoms 50 LCD-related symptoms 50 Intermittent problems 52 Undetermined problems 52
Chapter 5. Fn key combinations . . . 57
Chapter 7. Removing and replacing a FRU 65
Before servicing ThinkPad T420 and T420i . . . 66 1010 Battery pack 67 1020 ExpressCard blank bezel 68 1030 Serial Ultrabay Enhanced device or travel bezel 69 1040 Hard disk drive...
Hardware Maintenance Manual - Page 4
Notices 175
Electronic emissions notices 176 Trademarks 177
ii ThinkPad T420 and T420i Hardware Maintenance Manual 1150 Speaker assembly 95 1160 LCD unit 97 1170 Fan assembly 101 1180 CPU 105 1190 Base cover assembly and ...
Hardware Maintenance Manual - Page 5
Use this manual along with the advanced diagnostic tests to troubleshoot problems.
Important: This manual is intended only for the following ThinkPad® products. Before servicing a ThinkPad product, be sure to troubleshoot problems effectively. ThinkPad T420 and T420i Machine Type 4177, 4178, 4179, 4180, 4236, 4237, and 4238
Use this manual
This manual contains service...
Hardware Maintenance Manual - Page 6
iv ThinkPad T420 and T420i Hardware Maintenance Manual
Hardware Maintenance Manual - Page 8
... back. Attention: Another person must be there to lock the wall box in the safety sections of the units.
• If an electrical accident occurs:
2 ThinkPad T420 and T420i Hardware Maintenance Manual Stand on electrical equipment; Similar units to work area.
Attention: An electrical shock can cause personal injury and machine damage...
Hardware Maintenance Manual - Page 10
... handling ESD-sensitive parts: • Keep the parts in protective packages until they exceed the requirements noted here. 2. You can be verified by a certified electrician.
4 ThinkPad T420 and T420i Hardware Maintenance Manual The mat is required for operator safety and correct system function. Notes: 1.
Hardware Maintenance Manual - Page 12
Seek medical care if any interconnecting cables.
6 ThinkPad T420 and T420i Hardware Maintenance Manual DANGER If the LCD breaks and the fluid from the fluid are present after washing. DANGER Unless hot swap is ...
Hardware Maintenance Manual - Page 20
14 ThinkPad T420 and T420i Hardware Maintenance Manual
Hardware Maintenance Manual - Page 24
18 ThinkPad T420 and T420i Hardware Maintenance Manual
Hardware Maintenance Manual - Page 26
20 ThinkPad T420 and T420i Hardware Maintenance Manual
Hardware Maintenance Manual - Page 28
22 ThinkPad T420 and T420i Hardware Maintenance Manual
Hardware Maintenance Manual - Page 30
... overwritten. Attention: The drive startup sequence in the computer you are servicing may cause a system malfunction. Important notice for the computer you are servicing.
24 ThinkPad T420 and T420i Hardware Maintenance Manual How to use error message
Use the error codes displayed on the hard disk to diagnose failures. If more than...
Hardware Maintenance Manual - Page 32
.... 2. Click Product & Parts Detail and then follow the instructions on the screen to view the complete list of FRUs at the MT Model level.
26 ThinkPad T420 and T420i Hardware Maintenance Manual hard disk drive, system board, microprocessor, LCD, and memory) Use the HMM as a back-up to PEW and eSupport to...
Hardware Maintenance Manual - Page 34
...the machine failed 4. Date of service 3. Failure symptoms, error codes appearing on laptop products
The following symptoms might indicate damage caused by nonwarranted activities: • Missing ... Following is covered under the warranty by referring to excessive force,
or dropped.
28 ThinkPad T420 and T420i Hardware Maintenance Manual Name and phone number of the cosmetic parts •...
Hardware Maintenance Manual - Page 36
... comes up, immediately press F12 to select. Insert the PC-Doctor CD into the optical drive. 6.
otherwise, it cannot be sensed.
30 ThinkPad T420 and T420i Hardware Maintenance Manual If an error code appears, go to "Power system checkout" on page 37, and check the power sources. The main ...
Hardware Maintenance Manual - Page 38
... ThinkVantageToolbox also has problem determination aids that determine software and usage problems. For additional information about this program, see the Help for the program.
32 ThinkPad T420 and T420i Hardware Maintenance Manual Windows Vista® and Windows XP: Click Start ➙ All Programs ➙ ThinkVantage ➙ Lenovo ThinkVantage Toolbox Follow the instructions...
Hardware Maintenance Manual - Page 40
... also can
download the quick test programs from http://www.lenovo.com/diags.
To run a quick test using the downloaded program, do the following:
34 ThinkPad T420 and T420i Hardware Maintenance Manual Select the device class to troubleshoot and resolve computer problems. It combines diagnostic tests, system information collection, security status, and...
Hardware Maintenance Manual - Page 42
The diagnostic program will be launched automatically.
6. Use the arrow keys to use the diagnostic program.
36 ThinkPad T420 and T420i Hardware Maintenance Manual Follow the instructions on the screen to select ATAPI CDx (x: 0, 1, ...) and then press Enter. 5.
Hardware Maintenance Manual - Page 64
...LCD)
Notes:
This function is also available.
Enable the Full Screen Magnifier function.
58 ThinkPad T420 and T420i Hardware Maintenance Manual This function does not work while a DVD movie or ....
Change the settings of the hard disk drive.
On Windows Vista, the default brightness level is loaded after sleep (standby), hibernation, reboot, or detaching or attaching an...
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