Laptop with no fan has fan error

[Fixthat1]

We have been using this notebook for several years and last week it starts telling us there is a problem with the system fan at boot up.  There is NO FAN.  just an aluminum plate on the heat sink to conduct to the edge vents.  I put new thermal paste on, updated the BIOS,  held the power button with no battery or cord, The problem persists.  This is at startup, so it is cold.  Happens most, but not all the time.  How do I fix this ghost fan problem?

[EddyK]

Hello @Fixthat1,

Are you receiving a 90b or 90f fan error code?

According to the HP Notebook - 15-ac139ds's Maintenance and Service Guide as well as HP Partsurfer, there is indeed a fan assembly. 

More information about a fan error on HP notebook PCs can be found here. It may be necessary to replace the fan to continue the proper operation of the device's cooling system. 

Kind regards,

Eddy

[Fixthat1]

it is the 90b code.

The manual you mentioned covers several models as shown by several different heat sink and fan assemblies.

Here is the photos of each layer with no fan.

[EddyK]

Apologizes for the late reply @Fixthat1,

Yes, there doesn't seem to be a fan. The HP Partsurfer is incorrect and the manual just seems to be quite vague as it only specifies one fan assembly for all applicable models.

I did notice a very similar thread about a user having a fan error with a fanless laptop. The laptop was the same series as yours.

A lot of the threads about fan issues on this forum were resolved usually through extensive cleaning of the internals but it seems like you've already done that.

I'm afraid your only option may be to contact HP so they can thoroughly analyze your device. Otherwise, if the issue isn't too much of a nuisance, I would just leave it be.

Kind regards,

Eddy