Acer Predator PH315-54 / PH317-55 (LA-L191P) - Strange Fan Problem?

Hello

I have x4 motherboards 3x PH317-55 (NB.QB611.002) and 1x PH315-54 (NB.QC111.002), and on all of them the CPU and GPU fans do not work. The initial "stock" fans are rated for 5v 0.5A, but the VCC pin on the fan connector is 12v.

I have bought another brand new set of fans, these are also rated at 5v 0.5A and these also do not work, possibly the 12v burned the motor?

I also have a pair of fans from another different Predator model, that are rated for 12v and these fans work fine with the boards.

What i dont understand is why the voltage on the fan VCC pin is 12v when the stock fans are rated for only 5v?

Even in the schematic there is IC PU1201 that looks like it creates the 12v for the fans.






Can anybody help and explain?
Thank you

Hello!

These boards are designed for two types of fans - 5 or 12V. The type of fans is determined by the resistors RF4, RF7 (present for 5V fans) or RF27, RF28 (present for 12V fans).
All your boards are prepared for 12V fans, but someone most likely replaced the fans with the wrong ones - 5V instead of 12V.

You have two options:
1) Replace the fans with 12V ones.
2) Switch the resistors RF27, RF28 to the places of RF4, RF7 and use 5V fans.

Since the 5V fans were connected to 12V, they are very likely damaged.

Thank you for your advice, yes i can see it now. I think the boards having the same board number confused me. I will change the resistor layout to fit the appropriate fans.

Many thanks