The relay you need is a 5 blade double make and break. The fan would be connected to contact 87 and the LED to 87b. The two contacts are isolated from each other till the relay operates and provides power to them both via contact 30. Take a look at part number R30BD on this page.
http://www.vehicle-wiring-products.eu/VWP-onlinestore/relays/relays.php

You should be able to find a US supplier for the relay which is a standard Bosch type.

Stuart.


Last edited by Stuart_Giles; 05/27/2008 4:10 PM. Reason: spelling error
1950 Chevrolet 3100 (occasionally working) truck:https://c2.staticflickr.com/6/5490/30684982201_6dc479d18d_c.jpg
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