Failure classication by hardware devices and mechanical
Table 7-4 Failure classication by hardware devices and mechanical
4. Display 5. I/O devices 6. Storage 7. Mechanical
1. Display anomalies
on page 138
2. Dead pixel on page 140
3. No video (internal)
on page 140
d
4. No video (external)
on page 141
d
5. DisplayPort/VGA
on page 141
6. HDMI on page 141
7. No or bad external video
via docking on page 142
8. Incorrect or missing color/
distorted image
on page 142
9. Touch screen
on page 143
1. Keyboard on page 144
2. Keyboard point stick
on page 145
3. Keyboard backlight
on page 145
4. TouchPad on page 146
5. Network Connectivity
Ethernet (RJ-45 jack)
on page 146
6. Network connectivity
wireless (WLAN)
on page 147
7. WWAN on page 148
8. USB on page 149
9. Smart card reader
on page 150
10. Speaker, headphone -
audio issues on page 151
11. Thunderbolt (TB)
on page 152
1. Hard drive/solid-state
drive not recognized
on page 154
2. No boot to operating
system (no read/write
error) on page 154
3. Read-write error
on page 155
4. Slow performance
on page 136
c
5. Blue screen (BSOD) error
on page 155
b
6. Noisy hard drive
on page 156
1. Fan error message - 90B
on page 157
2. Noise (sound)
on page 158
3. Fan runs constantly
on page 159
4. HP Thermal Monitor
on page 109
5. Stuck power button
on page 160
b,c,d
similar symptoms
2. Examine the environment
It is important to examine the computer’s environment. If you can quickly identify the cause of the issue,
fewer resolution steps may be needed. Perform the following environment inspections:
● Check all cables and connections to be sure that there are no loose connections.
● Conrm that power sources are good, such as wall power type/adapter (110V/220V ac), power strip. Test
with a veried working AC outlet.
● Check for compatibility issues between the computer and third-party devices, peripherals, noncertied
devices, incompatible hardware (i.e., Mac OS device). Incompatibility can result in blue screen errors,
improper operation, and so on.
● Isolate the computer from sources of electromagnetic interference (EMI), such as cell phones, 2-way
radios, oor mats, fans (and other electronic motors). EMI may contribute to a display freeze issue or
lock-up.
104 Chapter 7 Troubleshooting guide