Fan on at Full Speed at Startup

[KGJUser]

I have an HP Pavilion dv7-4071nr laptop. I am running Windows 7 - 64 bit operating system. The BIOS version is F.29 dated 11/7/2011. I have started receiving an occasional cooling fan error, code 90B, on startup.

I am hoping someone can explain my computer's behavior and recommend a solution:

1) As soon as I turn on the laptop the fan starts operating at high speed. Even if the laptop is cold the fan will start operating at high speed.

2) The fan will continue to operate at high speed for as long as the computer is on. I can leave the computer just sitting there, running no applications, and the fan will continue to operate at high speed.

3) The computer does not feel warm. HWMonitor reports various temperatures around 50C.

Now for the interesting part:

4) If I pick up the laptop from the front, e.g, I grab the front of the laptop on opposite sides of the mouse pad and lift, the fan will slow down to a low speed, what I would call normal speed.

5) If I let the computer warm up, pick it up by the front to let the fan slow down, and then place it down just right, the fan will then seem to operate normally. It will speed up during heavier usage and slow down when the usage lessens.

6) At no time does the computer feel excessively warm.

Any explanation for this behavior? Bad fan? Bad connection?

Thank you.

[PHANIKUMARNV · Accepted solution]

HI

   its now time for the fan replacement but before goin to the conclusion i will give you few steps

1. please update the bios version from hp.com website by entering the product number of your computer under software and drivers.

2.then download the bios available for the computer and install it the fan spinning should come down if its same

3.then update the latest hpsa software on the computer then restart the computer i hope this should resolve the issue if not

 then its a time to replace the cooling fan on the computer.

Clicking the White Kudos star on the left is a way to say Thanks!

Clicking "Accept as Solution" on a Reply that solves your issue helps others who are searching
Although I work for HP, my posts and replies are my own opinion and not those of HP.

[AttackofZaq]

Hello KGJUser.

I agree with what PHANIKUMARNV said.  You are likely going to need to replace this fan.  The error generally means that the fan has stopped working altogether but in your case it is likely warning you that it is detecting issues and will fail.  

Here is a link to your notebook's Maintenance and Service Guide.  It will contain the information for disassembling and repairing the notebook.  It also normally has the part number information.  You can visit HP Part Surfer and use this information to purchase replacement parts.  

I hope this is helpful.  Have a great day!  

[KGJUser]

I replaced the fan two weeks ago and the computer is working well again. There was quite a bit of disassembly required to replace the fan but the procedure was well documented in HP’s Maintenance and Service Guide. Thank you again for your help.

[ArnoDK]

I had the same problem - the fan constant running at full speed when powering on the ZBook 15 G3.

I tried a lot of different things in BIOS and Windows update and such - nothing solved the issue.

The solution in my case was:

1: Start PC and log into Windows

2: Press and hold the Power Button for 30-40 seconds (the PC will shutdown after 5-10 seconds but keep pressing the power button)

3: Start PC again -> the fan was now "normal" again