Troubleshooting Guide
Troubleshooting Guide www.hp.com 2–9
Troubleshooting Without Diagnostics
System does not power 
on and the LEDs on the 
front of the computer 
are not flashing.
System unable to power 
on.
Press and hold the power button for 
less than 4 seconds. If the hard drive 
LED turns green, then:
1. Check that the voltage selector, 
located on the rear of the power 
supply on select models, is set to 
the appropriate voltage. Proper 
voltage setting depends on your 
region.
2. Remove the expansion cards one 
at a time until the 5V_aux light on 
the system board turns on.
3. 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 not turned on, then 
replace the power supply.
6. Replace the system board.
Solving General Problems (Continued)
Problem Cause Solution










