1. Power-on: Common issues are No Power, Recycle/Reboot, etc.
2. POST: Common issues are No Boot (have power), Light Flash or Diagnostics Error.
3. Performance: Common issues are Intermittent Loss of Power, Blue Screen, Hang, etc. In many cases, 
issues may be identied and associated with a particular hardware (i.e., display, storage).
Table 4 categorizes failures by hardware.
4. Display
5. I/O devices (Input/Output)
6. Storage
7. Mechanical
A single symptom can be listed under dierent groups. For example, No Video can belong to (1) Power-on or 
(4) Display; but Flickering when powered should be listed in (4) Display. Or, in another example, a blue screen 
can be caused by a driver conict in Performance (4), but it can also be caused by a defective hard drive under 
(6) Storage. Therefore, failures that share similar symptoms are noted..
If possible, make a record of the failure symptom, the phase of the boot-up sequence where the failure 
occurs, and the most likely location in the failure tree (Table 7-3 Failure classication by boot-up sequence 
on page 78 and Table 7-4 Failure classication by hardware devices and mechanical on page 79). This will 
help isolate the issue and indicate the next steps. For example, when the computer is running the operating 
system, it may experience an issue with (4) Display, (5) I/O devices (keyboard, wireless, and so on), (6) 
Storage, or (7) Mechanical components (stuck buttons, thermal shutdown, and so on).
NOTE: “Uncategorized” is used if an issue found is not listed. For example, Bluetooth is oered on certain 
hardware congurations; therefore, a Bluetooth issue can be classied under “I/O Device” if needed.
Failure classication by boot-up sequence
Table 
7-3  Failure classication by boot-up sequence
1. Power-on 2. POST 3. Performance
1. No Power on page 96
2. Intermittent power-on, shutdown, 
reboot on page 98
a
3. AC adapter issue on page 100
4. Battery not recognized, not charging 
on page 100
5. Battery discharges too fast 
on page 102
6. Burnt smell on page 103
1. No video (with power) 
on page 103
2. Blinking lights on page 104
3. Diagnostics error messages 
on page 105
4. BIOS password on page 106
1.
Intermittent shutdown on page 107
a
2.
Blue screen (BSOD) error on page 134
b
3. Freeze at Windows Logo (hang/lockup) 
on page 110
4. Electromagnetic Interference (EMI) 
on page 111
5. No wake up on page 112
6. Unresponsive on page 113
7.
Slow performance on page 113
c
8. HP Smart Adapter warning message 
on page 114
9. Incorrect time and date on page 114
a,b,c
 similar symptoms
   
78 Chapter 7   Troubleshooting guide