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> Fresh Air Relay, Wire from term 86?
tmc914
post Sep 22 2018, 07:28 PM
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Here is a picture from Prospero's Garage of the Fresh Air Fan Relay. The problem is, it does not say where the wire goes off to. Looked at the Fan switch wiring but all wires there are accounted for. Checked original manual and it says wire #14 but that does not make sense, or does it? Where does that wire go, what pulls in that relay?Attached Image
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Dave_Darling
post Sep 22 2018, 11:01 PM
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On the factory diagrams, there's a small "14" at the end of that wire. On the other page of the diagram, there's a wire with a small "14" next to it; it comes out of (or goes to) the headlight switch. It also appears to be fastened in to a plain red wire that goes to the turn signal switch.

Double-checked on the 73 wiring diagram after I noticed the year in your sig. Same thing there.

--DD
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Mike Bellis
post Sep 22 2018, 11:49 PM
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On just about ALL 12V relays, 85 & 86 are the on/off coil wires. 85 is the ground so 86 has to go to the switch that turns the fan on.
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tmc914
post Sep 23 2018, 04:33 PM
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Hi Dave, I see what you are saying and see the first "14", see picture below. Not sure by what you mean by it goes to the headlight switch because that does not make any sense. Are these diagrams accurate?

Mike, I agree that 85 (GND) and 86 are what pulls in the relay, but there is the rub. Can't find a diagram that shows where that 86 goes to. Before I get in and start tearing things apart it needs to make sense to me how it works.

Don't want to follow the wires on the car because it is supposed to be easier to follow the diagram. What gives. Anyone know where #14 really goes?
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Mike Bellis
post Sep 23 2018, 06:14 PM
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On the 74 diagram it shows it going direct to a switch. But the 74 does not call it a "fresh air relay". 74 calls it a heater blower relay. The fresh air controls in the dash is a 3 stage switch controlling fan speed.

Relay shown as J14

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tmc914
post Sep 23 2018, 07:12 PM
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Hi Mike, that diagram is very helpful. The one I have is cut into smaller pages and harder to follow. There are 2 fans, one is the heater fan that you mentioned and the other is the fresh air relay. It looks like power from the ignition switch goes to terminal #86 to pull in the coil for the fresh air relay. That would answer my original question of where wire number 14 goes (goes to ignition switch). When you turn on the car it allows the fresh air relay to turn on but then the 3 position fresh air switch runs the speed of the motor.

When I turn on my motor to high speed it smells like it is burning and drops the battery voltage down to 10.1 volts. I found the fresh air motor and it looks like it is going to suck to get to. It may not be the motor, it may be the wire connections that go into the motor. They looked cracked and brittle. Just another shitty little project to add to my to do list.

Thanks so much for the help. I knew someone or more would come through for me. Now it all makes sense. (IMG:style_emoticons/default/piratenanner.gif)
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Dave_Darling
post Sep 23 2018, 09:34 PM
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QUOTE(tmc914 @ Sep 23 2018, 03:33 PM) *

Hi Dave, I see what you are saying and see the first "14", see picture below. Not sure by what you mean by it goes to the headlight switch because that does not make any sense. Are these diagrams accurate?


The diagrams are accurate to my knowledge--until owners or mechanics start messing with the wiring!!

You have to look on the other page of the diagram to find the small "14" label. It's right above component #28, which is labeled "light switch". At that point, the wire is crimped together with a solid red wire that comes from the "X" terminal of the ignition switch. I'm pretty sure that carries switched power FROM the ignition switch.



QUOTE(Mike Bellis @ Sep 23 2018, 05:14 PM) *

On the 74 diagram it shows it going direct to a switch. But the 74 does not call it a "fresh air relay". 74 calls it a heater blower relay. ...
Relay shown as J14


Mike, the Heater Blower relay is on the relay board in the engine bay. The 74 diagram shows a "Fresh air blower relay", component J13, which is a relay on top of the fuse panel. That's the one referenced above, not the heater blower relay.


The "fresh air blower relay" is actually a misnomer, though. It's really a relay that supplies switched power to most stuff that needs switched power. Which does include the fresh air blower, but also includes a lot of other stuff as well....

--DD
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Mike Bellis
post Sep 23 2018, 11:18 PM
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Duh... You are correct sir. And, it goes to the headlight switch as you said... (IMG:style_emoticons/default/beerchug.gif)
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