Early heater fan wiring question, with bonus mystery wire Options

[r3dplanet]

My car has never had heat in the time that I've owned it. The car is a 1971 but the engine and wiring in the bay are all for 1973.

I took the time to completely refurb an early blower fan. It has two wires: one brown, one green. According to the wiring diagram I'm supposed to have wires directly from the harness to power it. I don't.

Where am I supposed to tap for power?

Also, on the relay board I have a mystery green wire coming from astern. I have no idea what it's for. Any guesses? See photos for clarity.

Thanks,
Marcus

[JeffBowlsby]

Hi Marcus...so you're the Schpankmeister huh? (IMG:style_emoticons/default/wink.gif)

The ignition harnesses are not all the same...to correct any misinformation. See my harness website for details. There are 3 Djet ignition harnesses and 1 Ljet ignition harness for our 914s. They are each different.

Issue: The 1970-72 cars main chassis harness does not have the wiring branch for the blower fan like the 1973-76 cars do. For the 1970-72 cars the fan connects to the ignition harness. For the 1973-76 cars the fan connects to a branch integral to the main chassis harness.

Easiest solution? Use a 1970-72 ignition harness to use the heater fan for an early 914. The only other way I can think of off the top of my head is to use the 73-76 ignition harness, then find the correct pin on the 12 pin connector for the (its either 10 or 11) for the green wire, then run a separate ground wire for the fan. You can study the two ignition harness diagrams and see what I am talking about. Or I can make a new or customize your existing harness to do the trick.

[r3dplanet]

Hi Marcus...so you're the Schpankmeister huh? (IMG:style_emoticons/default/wink.gif)

The ignition harnesses are not all the same...to correct any misinformation. See my harness website for details. There are 3 Djet ignition harnesses and 1 Ljet ignition harness for our 914s. They are each different.

Issue: The 1970-72 cars main chassis harness does not have the wiring branch for the blower fan like the 1973-76 cars do. For the 1970-72 cars the fan connects to the ignition harness. For the 1973-76 cars the fan connects to a branch integral to the main chassis harness.

Easiest solution? Use a 1970-72 ignition harness to use the heater fan for an early 914. The only other way I can think of off the top of my head is to use the 73-76 ignition harness, then find the correct pin on the 12 pin connector for the (its either 10 or 11) for the green wire, then run a separate ground wire for the fan. You can study the two ignition harness diagrams and see what I am talking about. Or I can make a new or customize your existing harness to do the trick.

Ack. It used to be that the Spankmeister thing was just born from irritation because all the other names I could think of were taken. Since then I've been using r3dplanet, but I can't change the name here. I'm stuck. And I'm not even into spanking.

Let me announce that I've made a blunder.

In fact, I believed all the harnesses I bought from you were in fact ordered for a 1971 model. The relay panel is still from 1973. I didn't know that my engine was a '73 until I was installing the harnesses this spring when I discovered that the harness came with a different throttle position pinout. When I looked at the engine code I discovered I had an EA engine - or 1973 1.7 liter.

So scratch all that information about having all 1973 wiring. The only '73 wiring I have is the relay board and injection harness. If the early ignition harness provides connections to the fan, then I'm even more confused because I don't see any connections.

This leaves me thinking that since I ordered the ignition harness a month after the purchase of the injection harness (when I made the EA engine discovery) I must have then ordered a '73 ignition harness. Thus, I have no fan connection at all because I have a late ignition harness (with no fan connection) and an early chassis harness that doesn't provide the connections either.

I apologize for the misinformation. It must be the new meds.

-marcus