Hi

An easy question for you.

I'm trying to get the heater fan to work on my 1973 914 2.0lt. The fan motor runs when I wire it direct to the battery. I have a wiring diagram that shows a switch but where is the switch on the car? Thanks - UKed

Small red pull up lever just south of the shifter. There's a small square black cover next to it that says Defrost on off. Pull up it starts the fan

There should be a green wire attached to the lever. When you pull the lever it completes the circuit to ground.

Brilliant thanks Steuspeed. i will remove the central console and have a look.

and thanks to Bandjoey

Just more info: the green wire in the tunnel under the shifter may be hiding in there. Fish it out with a dental pick or something. It should connect to the tab on the heater lever in bandjoey's picture. When the lever is pulled up far enough ("max" heat) that green wire will ground the relay that's farthest back on the relay board (IIRC) via pin 11 on the 14 pin connector. That relay then provides power to the fan. So, if it's not working check: the green wire is connected, the lever is far enough up, the 14 pin-connector is connected, the relay is getting power, and the relay itself is serviceable.

At least that's my understanding of how it works.

I just went through this. The URO fan relay had a broken post inside. New relay took care of it.

And yes, it is the rear-most relay.

Rob mine is redundant now as I have headers on my six ,but the wire I had connected was black when I got the car from the PO.
I would like to use it to as a switch for a small electric defroster I will install,did the wire colour change for different years or did I just find the wrong one on there ?

Hey Porschetub! Pretty sure that wire is green/white on all years, but I could be wrong. Checking back on the wiring diagrams, I see it actually goes to pin 9 on the 14 pin connector (not 11 like I said in post above). Check the continuity between those two to be sure.

A URO part was bad? Color me shocked! </sarcasm>

--DD