Corsair H110i faulty coolant temp sensor?

[nikvin]

Hej alla,

 

I don't really know if this forum is the right place to ask (if not I'd appreciate you could direct me), but I'll try.

Some time ago got a used Corsair H110i (in a nice and working condition according to the seller, for reasonable second-hand market price).

I've used it together with i5-9600K in a build today, to find out that the fans are spinning at 100% no matter what I do. First I thought it was a relatively known issue with the communication between the iCUE software and the pump, but iCUE seems to talk correctly to the device... except for the coolant temp is sharp 100 C. I presume it is the sensor issue (or the cable issue?) bc the processor temp is around 30-35 idle, which would not be the case should there be no coolant at all, or insufficient flow due to the bubble/clogging/etc... Also the temp of the coolant is 100 C sharp, no variations, which also makes me feel it is either a sensor, cable, or communication issue. Tried re-plugging in a different USB port on the MB, unfortunately, no result.

Any ideas except for throwing it away? Anyone had a similar experience? Be grateful for suggestions :3

Thanks for taking your time to read

[c-attack]

Try a forced firmware update. Go to the CUE settings gear -> firmware -> check for update. It will come back up to date or latest, but reveal a 3 dot drop down menu. Choose force update and it will reload the current firmware. That should reset things for the moment.

 

This is not a common issue with any AIO series, but is possible. However it’s most commonly seen as software interference. Make sure you are not running HWinfo, Aida, or another monitoring program that polls the H110i. They fight over access and loss of fan control and garbage data are common consequences. 
 

If it’s going to stick at 100C, you won’t be able to use its fan controller. You’ll need to move the fans to the motherboard for control. 

[nikvin]

Thanks a lot! Do you know if these coolers have an internal PLC that would react to the coolant sensor readings? - I have tried running the thing through MOBO yesterday and it kinda works, but it seems like no matter what the pump is at max RPMs (smth around 3300 if I rememebr correctly). Not like it bothers me much, the pump itself is quiet, but I presume it unnecessary consumes the pump resource? And another (stupid) question - the pump takes the power from the SATA, right? then why there is a 3-pin connector to the 12V fan socket on mobo with clearly only one single wire in it?

Thanks again, I'll try force update, but leaning towards controlling from mobo/bios

Best

[c-attack]

The 3 pin is really a one wire tachometer sensor for cpu fan. This satisfies the standard “cpu boot error” protection feature on most motherboards. There is no requirement to use it and it has no effect on AIO operation, but your motherboard will yell if nothing is on cpu fan. Most bios versions let you disable cpu boot protection. 
 

The AIO definitely has an internal circuit board with a fan and pump profile plus some emergency reaction settings, much like a PSU. Even with no software present, it will kick into max mode at a specific temp. It originally was 40C but I think it moved up to 45 with a later firmware. I am hoping the firmware flash will reset the alarm state and drop it back into normal mode, but if the sensor truly is wonky, it will slam right back to max after the update.