Table 7-1  Troubleshooting methodology and general troubleshooting steps
Identify issue Analyze issue Resolve issue Verify solution
4. Update BIOS and drivers 
on page 80
7. Status lights, blinking light 
codes, troubleshooting lights, 
and POST error messages 
on page 85
11. Test with minimum conguration 
on page 92
12. Test with veried working 
conguration (hardware and/or operating 
system) on page 93
13. Replace the system board on page 93
Identify the issue
1. Understand the issue
It is important to understand the issue that occurred, including related symptoms. It helps to understand the 
basic computer boot-up sequence as well as the failure itself. The boot-up sequence and associated failures 
are described below.
Boot up sequence
The computer performs several steps after you press the power button or restart the computer.
It is important to understand where in the boot-up sequence the symptoms occur. The following table lists 
the phases of the boot-up sequence and explains the symptoms that may occur in each phase. For example, a 
blue screen error (BSOD) often occurs during the performance phase.
Table 
7-2  Boot-up sequence
Item Description
Power-on After power button is pressed, the computer boots after all internal power rails (i.e., 5V, 3.3V) are stable.
Conrm that power lights are on fan is spinning.
Next step: If the computer experiences a power-on issue, see “Verify Power Good (Troubleshooting) lights” in 
No Power on page 96.
Common issues: all lights are o; troubleshooting lights are on; does not boot; video is absent.
POST (UEFI/BIOS) Power-On Self-Test (POST) veries that hardware components (processor, hard drive, memory, etc.) are 
functional. When POST is complete, the HP logo displays briey and then disappears.
If there are errors, the computer may exhibit blinking lights and POST error messages
Common issues: lights blink, error message appears, hangs.
Performance 
(operating system)
System boots to operating system, and Windows logo screen appears..
Common issues: hangs (lock up/freezes), blue screen, video distorted, driver conict, slow performance, 
display issue (dead pixel), I/O issue (no speaker sound), wireless/audio unavailable, noise.
See Analyze the issue on page 80 table below for detailed troubleshooting information).
Failure classication
Failure classication is a breakdown of dierent types of failures and symptoms that could occur during the 
boot-up sequence. Table 3 and table 4 represent the failure classication for common notebook failures.
Table 3 categorizes failures by the boot-up sequence.
General troubleshooting steps 77