Caanot get rid of error code 512 rear chassis fan not detected

[retired911guy]

My liquid cooling fan started slowing down.  I blew the dust out of every place I could access and have installed 2 different new PWM 4 pin variable speed fans on the radiator.  Neither cleared the error message, even 2 of them tied togerher with a splitter.  BIOS only lets me look at the fan speed under "THERMAL" heading.  Fan is working normally.  Even replaced the liquid cooling system.  I still have to press F1 to boot the computer due to the error code being generated.  It's like "once it's there, it's there forever"!  Is it even possible to remove the error code?  The computer is only just over 2 years old.  I cannot access, read or modify the bootlog to see if the code is there and I'm not sure I'd know what to do if I could.  What can I do?  Must I buy a new PC to get rid of it?  Help me, PLEASE!!

[CF4]

Hi

I have never has the thermal paste (or silpad) on the CPU fail, but I do understand it can can degrade.

So is the CPU running hot?

I would use Piriforn Speccy myself for something like this...

CPU
        AMD A6-6310
            Cores    4
            Threads    4
        
            Stock Core Speed    1800 MHz
            Stock Bus Speed    100 MHz
            Average Temperature    39 °C

[retired911guy]

How on earth did you get the CPU was running hot and it was due to thermal paste, from what I wrote??   That was an awesome reading 'way down between the lines!!  Seriously, everything was fixed, the computer is running normally, except it hangs on boot up and says "rear chassis fan not detected" and I have to press F1 to boot up.  I can't get rid of the error message and boot up normally.

[retired911guy]

Sorry, I did the same thing you did.  I didn't read your post correctly.  The CPU is not running hot, the radiator, fan and cooling system are all functioning normally, and I used top quality thermal paste on the contact surface.  Brand new, not degraded.  Only problem is I can't  clear error message and get a normal boot up.

[mdklassen]

> it hangs on boot up and says "rear chassis fan not detected" and I have to press F1 to boot up. 

To ask the obvious: is there a fan directly connected to the power-pins on the motherboard labelled "rear chassis fan" ?

I have seen a machinist's computer. 

He cut a hole in the side-plate, mounted a fan in it, and wired the fan to the "rear chassis fan" power-pins, since there was no room inside the chassis for this extra fan.

[retired911guy]

There is no connector on the MB labeled "rear chassis fan".  Came from factory with liquid cooling system.  Original fan was connected to "CPU FAN"; connector next to it was labeled "PUMP - FAN".  Radiator, pump/CPU cooling plate and fan have all been replaced and are connected to appropriate/correct connectors on MB.  Error code still generated, still have to fress F1 to boot it up but everything is otherwise working normally.  CPU not overheating.  Only occasionally hear fan speed up a bit.  Only other fan connector on MB is "VRM FAN", a 3 pin connector for a voltage regulator module fan , which this PC has never had or needed.  It's like the "512-rear chassis fan not detected" code is etched in stone and will forever more be with me.  My last resort is to hook up a REAL chassis fan to connector (constant speed, 120 mm regular fan) to the CPU FAN connector and see if that will clear the code.  I don't know what else to do, other than just junk it and get a new PC simply because I can't clear an error message that the cause of which has been corrected.  HP really blew it by not allowing such an operation.

[mdklassen]

> connector next to it was labeled "PUMP - FAN". 

> ... pump ... fan have all been replaced

> and are connected to appropriate/correct connectors on MB. 

> Error code still generated.

Did you replace the fan with a "Genuine HP" part?

If not, then the replacement is not responding to the motherboard's "query".

Not getting a response, or getting an incorrect response, the motherboard declares "not present".

Try temporarily connecting any "ordinary" 3-wire fan to that connector.  Does that make the motherboard "happy" ?

[retired911guy]

Part not available from HP.  Just try finding a new/replacement HP liquid cooling system for the ENVY Phoenix 860.  I found only one place in the world that had them.  Fan was an exact replacement in all specs.  Tried the one that came with the LCS and even bought a separate one, no change.  Trying next, as indicated in previous post, a real chassis fan.  It's possible, but I truly doubt it, that a genuine HP fan would make a difference.  Thanks!

[retired911guy]

Well, after reading your post and some diligent searching, I did find the exact replacement fan, made by the same manufacturer, in China, for just less than $38.  The only difference in specs that I can find is that the current draw on this fan is 1.2A, which is about double what the fans I have tried draw.  Maybe that is the key?  They advertise the correct HP part number.  It's worth a shot.  In for a penny, in for a pound, as they say.  That would be the fifth fan I will have purchased.  Bought 4 already.