Radiator Fan Switch

[Dharn55]

i recently ran the wires for adding switches to run the radiator fans and the engine compartment fans. I was going to use a Footwell Light Switch, but when I tried it the fans only ran when the switch was held down. Apparently it was designed to control a relay and it not a simple on/off switch. Does anyone know of a Porsche tip switch which will accomplish this, i.e. keep the fans on until I switch them off. I would prefer not to mount a non-standard switch.

[Sandy]

i recently ran the wires for adding switches to run the radiator fans and the engine compartment fans. I was going to use a Footwell Light Switch, but when I tried it the fans only ran when the switch was held down. Apparently it was designed to control a relay and it not a simple on/off switch. Does anyone know of a Porsche tip switch which will accomplish this, i.e. keep the fans on until I switch them off. I would prefer not to mount a non-standard switch.

I don't know of any 986 or 996 toggle switch which mechanically latches, however, a latching relay circuit might be in order. Take a look at the info I posted awhile back:

http://www.renntech.org/forums/index.php?showtopic=2245&hl=

Be careful to observe the current limitation of the contacts on the latching relay as well as the source of +12 volts.

You will probably want the amber LED in the FWL switch to illuminate when the relay is "set," or "on," rather than "reset," or "off. Consequently, you will need to connect the wire coming from pin 5 of the FWL switch to pin 5 of the relay, instead of to pin 1, as I drew it for David T.