HP t100 Maintenance And Service Manual page 178

System does not power on and the LEDs on the front of the computer are not flashing.
Cause
System unable to power on.
168 Appendix K Troubleshooting Hardware
Solution
Press and hold the power button for less than 4 seconds. If the
hard drive LED turns green, then:
1.
Remove the expansion cards one at a time until the
5V_aux light on the system board turns on.
2.
Replace the system board.
OR
Press and hold the power button for less than 4 seconds. If the
hard drive LED does not turn on green then:
1.
Check that the unit is plugged into a working AC outlet.
2. Open hood and check that the power button harness is
properly connected to the system board.
3. Check that both power supply cables are properly
connected to the system board.
4. Check to see if the 5V_aux light on the system board is
turned on. If it is turned on, then replace the power
button harness.
5.
If the 5V_aux light on the system board is off, then
replace the power supply.
6.
Replace the system board.