I have a custom built Saldana radiator with shroud and built in SPAL fan. I would like to hook the wiring in coming off the fan to the factory system so that it operates to OE specifications. Fans cuts on when when temp reaches __°F. Where would i wore into to make that happen? Thanks in advance

-Jason

 

Do you have a three speed fan?

 

I don't know. But i wouldn't think so, being the wiring coming off the fan has just two prongs for power and ground.

 

Spa fans are single speed.
I ran the Saldana shop for 4 years.
To wire the fans right you have to remove the 4 factory relays and replace with 1 or 2 Spa relays pending on number of fans. This also requires the install of 3 BMW 1-way diodes. There are 3 wires that control the fans to ground - 1) ECU, 2) Thermal switch, 3) AC switch. The ECU and the Thermal switch cross talk when wired together and turn the fans on immediately when power is applied. You only need 2 of the BMW 1-way diodes the third one is just for safety. This took some time to figure out on mine with the FSM wiring diagram. This setup has worked great for years now.

 

Before:


After:


you do not need any diodes as all switches for the fans are switched grounds.

Brad.

 

Sorry to bring this back up but to confirm I'd need to connect the light green wire to the white pink the the black earth from the fans to them then the power would be the yellow white to the power for the spal fans as my v mount comes with 2 wire spal fans

 

Probably the simplest would be the R/Y wire coming off Relay 2. That relay is controlled by the ECU. If you have a PowerFC you can set that temp where the fans turn on. If you have another ECU there most likely is a fan output and the wiring would be right there for fan control.

I will state that most aftermarket fans are crap. Super loud, not reliable, and don't cool that well. Stock fans are the best way to go if at all possible. If you have aftermarket fans prepare to fight with some aspect of them regularly.

Dale

 

No problem so if I use the R/Y to trigger the fans to come on when my power fc requires them to and ground them using which wire the diagrams I've got aren't very clear on my phone

 

R/Y from the fan relay to the 12v side of the fan, then ground wire to a good chassis ground. Set all the temps on the PFC to the same and you're good. You can also set the temps in the PFC to like 0 degrees to test it out and make sure it works right.

Dale