Toshiba Satellite U900 Maintenance Manual page 45

2 Troubleshooting Procedures
Check 3 Make sure that the DC-IN input port socket is firmly secured to the system board
of the computer.
If the DC-IN input socket is loose, go to Procedure 5.
If it is not loose, go to Check 4.
Check 4 Use a multi-meter to make sure that the AC adaptor output voltage is close to 19
V. If the output is several percent lower than 19 V, go to Check 5. If the output
is close to 19 V, go to Check 6.
Check 5 Connect a new AC adaptor or AC power cord.
If the DC-IN LED does not light, go to Procedure 4.
If the battery LED does not light, go to Check 6.
Check 6 Make sure the battery pack is installed in the computer correctly. If the battery is
properly installed and the battery LED still does not light, go to Procedure 4.
Procedure 4 Diagnostic check
The power supply may not charge the battery pack. Perform the following procedures:
1. Reinstall the battery pack.
2. Attach the AC adaptor and turn on the power. If you cannot turn on the power, go to
Procedure 5.
3. Run the Diagnostic test following the procedures described in Chapter 3, Tests and
Diagnostics. If no problem is detected, the battery is functioning normally.
Procedure 5 Replacement check
The system board may be disconnected or damaged. Disassemble the computer following the
steps described in Chapter 4, Replacement Procedures. Check the connection between the AC
adaptor and the system board. After checking the connection, perform Check 1:
Check 1 Use a multi-meter to make sure that the fuses on the system board are not blown.
If a fuse is not blown, go to Check 2. If a fuse is blown, go to Check 3.
Check 2 Make sure that the battery cable is firmly connected to the system board. If it is
connected firmly, go to Check 3.
Check 3 The system board may be damaged. Replace it with a new one following the
instructions in Chapter 4.
Satellite U900/U940/U945 Series Maintenance Manual
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