Pump not starting

[valve]

I just finished my custom loop and went on to leak test my system. I unplugged the ssd, cpu, gpu cables and jumped the motherboard. However, when I switched on my psu (whose fans are spinning fine), nothing happens, not a single noise from my ek d5 pump. I powered the pump by connecting the pwm cable to the CPU_OPT header and the molex to a molex cable connected to the PERIF1 port of the psu. What could I have possible done wrong...?

[bignaz]

Got any other cables or ports on your psu? 

 

I wouldn't be surprised if the pump is doa knowing EK. 

 

Run it without the pwm to the mobo? Could be a bios issue with the fan speeds. 

[valve]

11 minutes ago, bignaz said:

Got any other cables or ports on your psu? 

 

I wouldn't be surprised if the pump is doa knowing EK. 

 

Run it without the pwm to the mobo? Could be a bios issue with the fan speeds. 

I have some other cables connected to the psu but not to the mobo

How would I test a faulty pump?

it still didn’t work without the pwm cables

[bignaz]

Without the pwm connected it should run at 100%.  Are you sure that 4 pin is sending power to the pump?