Toshiba PORTEGE M400 - Manual (Page 101)

2.16 Tablet Pen Troubleshooting 2 Troubleshooting
Procedure 3 Connector Check and Replacement Check
The Digitizer and LCD are connected to the System board as below.
Check 1 The Digitizer may be disconnected. Make sure the Digitizer is connected to the
CN9540 on the System board. If there is still an error, go to Check 2.
Check 2 The Digitizer or the System board may be defective. Replace it with a new one
following the steps in Chapter 4. Then check the tablet pen is working properly.
PORTEGE M400 Maintenance Manual (960-541) [CONFIDENTIAL] 2-53