Question I need help with my water cooler it wont light up

May 5, 2019
My coolermaster ml240l rgb water cooler wont light up. In the instructions it showed stuff but the stuff wasn't on my motherboard. If you know anything about this please help me.

Text me at [don' t post your phone# on the forum] for a photo of what it looks like on the motherboard
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That AIO system comes with its own manual controller box for the 4-pin plain RGB lighting components of the two radiator fans AND the pump unit. EACH fan PLUS the pump has TWO cables from it - one for the fan motor (or pump motor), and another for the RGB lighting components in each. The pump's motor connector goes into a mobo header for power, and there is a fan Splitter you use to connect both fan motors to a single CPU_FAN header. Then you have a separate RGB Splitter and some gender-changer adapters you must use to connect BOTH the rad fans AND the pump's RGB cable to the manual Controller module. That is how the pump's RGB units get power and control. From your pictures it appears you have the two rad fans operating AND lit under control, so that system works. Check the connection from the pump's RGB cable to the Controller RGB Splitter.


Cooler Master Masterliquid ML240L RGB on

Pump goes to cpu_opt.
Pump rgb goes to RGB splitter.
Fan RGB goes to RGB splitter.
RGB splitter goes to RGB controller.
Fans go to cpu_fan via 2way fan splitter.

Fans get controlled by either Corsair's iCue software, SpeedFan, bios, motherboard fan software.

RGB is seperately controlled by the manual controller.


Find the RGB header since that is a Gigabyte Aorus motherboard and should have a RGB header somewhere, which will go to the RGB splitter and you do not need the manual controller.
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