Mechanical - HP ZBook x2 Manual

Mechanical

Fan error message - 90B
Items
Symptoms
Fan error 90B at boot
CAUTION: May lead to system shutdown, data
loss or possible system damage.
Note
Procedures
Possible causes
Defective fan; out-of-date BIOS.
The system fan is not spinning or not spinning properly (loose connection, fan
●
is stuck or defective).
● The temperature inside the case is too high, and the fan cannot spin fast
enough to remove the heat due to an obstruction to air flow.
Troubleshooting steps
General actions
1. Update BIOS and drivers (4. Update BIOS and drivers on page
to default. BIOS may implement new fan characteristics and updates for other
components.
2. Perform a hard reset (8. Hard reset on page
reset recorded thermal values in memory.
Thermal-related issue
1. Verify thermal condition:
a. Check fan and connection. Reseat fan cable.
b. Be sure that no obstructions or dust are in heat sink fan, fin, or vent.
c. Test fan using HP PC Hardware Diagnostics (UEFI) tool
Diagnostics and Tools on page
loud noise and that fan blades spin correctly.
d. Test with a verified working fan.
e. Remove old thermal compound and pads, and replace properly with new
pads.
2. Verify thermal solution
Use Thermal Monitor tool (available only to authorized service providers/
▲
technicians) to run stress test (processor and GPU) and verify that
thermal sensors are within limits after thermal condition is serviced.
BIOS currently omits fan presence detection to shorten boot time delay less than
four seconds. Therefore, the fan error is generated based on previous boot to
operating system that found system fan error.
Fan often is part of thermal solution, including heat sink, fin/ muffler, and thermal
grease. Fan replacement requires reboot and fan function verification using HP PC
Hardware Diagnostics (UEFI) tool.
Common issues and possible solutions 115
63) or reset BIOS
70). Performing a hard reset can
(6. HP Hardware
64). Be sure that the fan is not producing