Toshiba 650CT Maintenance Manual page 53

Procedure 2 Connector Check and Replacement Check
The DAA board is connected to the modem I/F board. If the modem malfunctions, there may
be a bad connection between the DAA board and the system board, or the DAA module or
system board might be damaged.
Disassemble the computer following the steps described in Chapter 4, Replacement Proce-
dures, and perform the following checks:
Check 1 Make sure DAA board PJ1 is firmly connected to I/O board PJ1, and that I/O
board PJ5 is firmly connected to system board PJ18.
DAA board PJ1
If a connector is disconnected, connect it to the system unit and repeat Procedure
1. If the DAA board is still not functioning properly, perform Check 2.
Check 2 The DAA board may be defective or damaged. Replace the DAA board with a
new one following the steps in Chapter 4, Replacement Procedures. If the DAA
board is still not functioning properly, perform Check 3.
Check 3 Replace the I/O board with a new one following the steps in Chapter 4, Replace-
ment Procedures. If the modem is still not functioning properly, perform Check
4.
Check 4 Replace the system board with a new one following the steps in Chapter 4,
Replacement Procedures.
650CT
PJ1 I/O board PJ5 PJ18 System board
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