Dewitts Spal Brushless Fans Problem

[Monte_ExpreSS]

Anyone here running Spal Brushless fans with their sbl-ts temperature sensor? I bought a set of the 12” fans from dewitts. The temp sensor includes a 12v override wire that can be used to run the fans on high speed. I tied that into my a/c pressure switch.
When the vehicle is cold, running or just key on the override turns the fan on high. If I let the car come up to temp, the fans kick on, gradually ramp up speed and cool the car off. Problem Im having is it only works 1 time!! Once they cycle one time, they never turn on again. I have to wait for the car to fully cool off before they will restart.
For testing purposes, I bought a second sensor to try, but it didnt change.
I have the main power for the fans ran to the alternator stud as my battery is mounted in the trunk.
Confirmed 14.2v at power source for fans, and all other connections are soldiered and heat shrinked.
Spoke with Brent at Spal, and he suggested powering the fans directly to the battery. Tried that as well but no change.
Not sure where to go from here.

https://www.dewitts.com/collections/brushless-fans/products/dewitts-dual-12-brushless-fan-kit?fbclid=IwAR2vN0mTdq8M928_Anitf9FX7LraFXt6JgwLC ecllVDGeFJylSxxz43W5Cs

[dhutton]

So your car is overheating because the fans aren’t turning back on? What fan temperature sensor and what temperature thermostat? I see you are in Canada, what is the ambient temperature when you are doing this?

Monitor the radiator hose temperatures with an IR temperature meter.

Don

[Monte_ExpreSS]

Yes the temp continues to climb with no fan operation. The fans will not respond to coolant temp increase or the 12v override wire when this happens.
It should be noted that the change over to these fans were not because of any previous cooling issues, it was simply a winter time upgrade because I wanted to take advantage of the pwm control.
the controller/sensor Im using is Spals spl-ts-195p which is included in the kit. I also verified with spal that this was a compatible controller.

I am in Canada, temp is just above freezing right now, 32f. Im
monitoring coolant temp at the moment through autometer invision dash, as well as hp tuners. Both are run off of separate sensors and read within 1* of each other.

both upper and lower rad hoses are hot so I know the thermostat is operating and coolant is circulating. Thermostat is a 160* motorad. The spal controller operates between 175-195* so it should be matched to the operating range.

again, the move to these fans was not because of any previous cooling issues, the car has always ran fine without overheating

[dhutton]

What if you disconnect the override from the binary switch? Do the fans operate normally?

Have you tried connecting to the other side of the binary switch?

I had something strange happen with the old Entropy fan controller and had to put a diode in series with the signal from the binary switch to get it working right when I connected it to the AC sense input on the Entropy controller.

Don

[cpd004]

I have the same sensor running dual fans. I'm not running the override at the moment. I'd definitely try what Don just said.

Also, these fans draw quite a bit of power. I can't imagine running them at full speed with the AC on for very long.

Is the sensor grounded at the same place (stud, screw, etc.) as the fans?

It sounds like something internal to the fans is seeing a fault and not letting them restart. Maybe that ground?

[Monte_ExpreSS]

Update: figured out the issue. Apparently the sensor was not happy with the location of the 12v keyed red wire. I moved it directly to the battery and the fans work flawlessly. Now to find a better location for a key on 12v source.
I will say, these fans are awesome! The pwm control works perfectly and man do they move some air on high speed.
Thanks to all who responded

[dhutton]

Nice work!

Don