PSU is operational, but PSU with pump shows no operation (Leaktest with extended PSU)
PSU is operational, but PSU with pump shows no operation (Leaktest with extended PSU)
Hey there! After spending 6 hours trying without results, I’m reaching out for your assistance.
In this setup:
Power supply unit: Thermaltake 630W, Corsair SF750
Cables: Standard 4-pin Molex cable
Pump: Regular Alphacool D5 pump
Tool to interrupt the circuit: Paperclip
My goal is to leaktest my custom loop by linking two pins of the D5 pump to an external PSU and...
Here’s what I’m experiencing:
The PSU works perfectly when I short the circuit with a paperclip.
On my multimeter, the Molex wires display 5V and 12V.
So it seems the PSU is functioning correctly.
But when I connect the red and black pins of the D5 pump to the PSU’s 4-pin Molex and power it back on, nothing happens.
The PSU isn’t supplying any power, and the power cables read 0V.
When I disconnect the pump, the PSU appears to work again when I turn the switch back on.
This inconsistency is confusing me.
Am I missing something here? Am I really making a mistake by running this leaktest?
Thank you very much for your help!
9 volts?
I wouldn't have imagined that...
FYI:
https://www.lifewire.com/molex-4-pin-per...ut-2624582
See Molex pin list, wire colors, and voltages.
This PSU?
https://www.amazon.com/ThermalTake-SMART...B00BDBZH3A
You referred to an external PSU – is there also an internal one?
If you've used any modular power cables from different makes and models, those might be involved.
Attempt to sketch the connections from the external PSU to the pump.
I suggest stopping all further efforts until the correct connections and pins are identified and verified as safe.
You might be just a wire or pin away from a bad outcome...
Thank you for your input. I have two external PSUs ready for leak testing: the Corsair SF750 W and the ThermalTake Smart Modular 630W.
The internal PSU (V1100 SFX Cooler Master) is currently linked to all other parts of the system.
I don’t have any original power cables left for the ThermalTake 630W; I’m using the cables from the Corsair SF750 W or the V1100 SFX Cooler Master.
Right now, I only see a few wires with colors—just two loose pins (red and black) besides the ones coming out of the pump.
Modular power cables aren't one-size-fits-all. Using a cable from an incompatible power supply greatly increases the chance of damage, unless you're certain the connector layout matches exactly.
I see. The Corsair PSU comes with its original power cables, so the setup should work fine. From the pictures you shared, the PSU shows a 12V output with the original cables connected. To confirm if anything was damaged, check for any burnt marks or abnormal connections.
I am worried that employing modular power cables from various PSUs could be the reason behind the issue.
12 volts minus 3 volts equals 9 volts.
Draw some wiring diagrams or connections to see how this 9 volt reading might occur.
Check the pinout on the Molex connectors, ensuring each pin matches its corresponding pin: Pin 1 with Pin 1, Pin 2 with Pin 2, etc.
Make sure the pinouts are accurate before making any connections.
Is it Type 4? The 9-volt reading was shown on the ThermalTake 630W, not on the Corsair Psu.
9 volts being out of tolerance - is that correct?
Reference links:
https://www.lifewire.com/how-to-manually...er-2626158
Check the tolerances.
https://www.lifewire.com/power-supply-vo...es-2624583
The situation is that this pump was previously connected to the same PSU (Corsair SF750) and fully part of the PC setup. Recently, I purchased a more powerful PSU (V1100 Cooler Master) to improve system stability since my previous unit was providing inadequate power and causing frequent system crashes. The pump from then on was always running, except for the growing number of failures. At that time, it was audible and operational with the Corsair PSU. Now I intend to use the Corsair PSU as an external source to test for leaks in my loop. I’m uncertain about my approach, mainly because I’m still learning about tolerances and repair safety.