Thermo fan for E30

[Doughnut]

My 323i e30 has air conditioning standard, (with the condenser and electric fan out front) How would i go about wiring this fan on a separate circuit to switch the fan on and off without operating the a/c?.

What i mean is. How do i switch just the fan on to get a little more cooling to the engine, without the a/c being on.

thanks to anyone that can help.

 

[cali_e30]

You dont have a button that switches the A/C on/off?

 

[Doughnut]

Yes i do have the button that switches the a/c on and off, however the air conditioning takes away a considerable amount of engine power and generates more engine heat.
All i want to be able to do is, when im not using the a/c, I want to be able to switch just the a/c's thermo fan on and off, without using the a/c itself.
I want to get in idea of how to wire this up.