AC fan wiring

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73c20jim

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Where does the orange wire from the main climate control attach to the fan, It is orange wire #52.
 

chengny

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Where does the orange wire from the main climate control attach to the fan, It is orange wire #52.

Power on 52 ORN doesn't go directly to the blower motor. It connects to the blower relay and is used to energize the coil inside the relay. When the relay pulls in full battery voltage is applied to the motor windings. See the attached, the first one isn't exactly your year but the operation is the same.
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Here is the dwg applicable to your year. The 40 ORN serves the same purpose as the 5 RED in the above dwg:

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73c20jim

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Is the blower relay under the dash. I would have to assume so since the wire is so short.
 

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The relay should be under the hood, mounted to the blower box.
 

chengny

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The relay should be under the hood, mounted to the blower box.


X2 - there are two components mounted to the outboard side of the evaporator housing. The relay and a thermostatic control switch. The relay is the upper of the two:

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73c20jim

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OK. We might have gotten off course here.

There is an orange wire going from the four prong fan plug to the blower relay. I got that one covered.

There is another orange 52 wire coming from the climate control switch going into a connector. The wire is about four inches long. That's the one that I don't know where it goes.

Maybe to ignition switched or 12v hot???

It the second diagram extreme right/middle is a lonely wire coming off the master switch, not the fan switch, marked orange 52 to connector 2977253. What does that connect to???
 
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73c20jim

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Here is stupid orange wire to nowhere.

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chengny

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With the mode select lever is set to AC - and the temperature control lever is in the full COLD position - the blower speed switch is bypassed and only HI speed is available. There is a switch in the mode selector that closes when the above conditions are present. Full battery voltage is then applied to the ORN 52 via the ORN 16:

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I can't tell from the image provided which end of the ORN 16 is disconnected but the fan speed switch should have a 5th terminal for that lead. And there is one terminal on the selector switch that is separate from the 3 stab connector - that would be used to connect ORN 16.
 

73c20jim

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Took climate control unit out of spot. Took fan switch off unit. Only 4 connectors. Went to parts truck. Did same. Only 4 connectors.

Its a four stab connector. Harness plugs into it. No extra blade.
 

chengny

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Took climate control unit out of spot. Took fan switch off unit. Only 4 connectors. Went to parts truck. Did same. Only 4 connectors.

Its a four stab connector. Harness plugs into it. No extra blade.


IDK what to tell you then. Is the other end connected to the selector switch? I wouldn't worry about it - the fan speed will just be in manual control. Its probably always been like that anyway.
 

gmachinz

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How long is that orange wire? Looks like its 14ga in which case it might be your cigg lighter power.
 

gmachinz

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You can use a multi-meter set to ohms and at least track down its circuit at the fuse panel.
 

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Or do what I did and pull all that endless mess of wires, hoses and cables out. Throw the whole pile of junk in the trash and install a Vintage Air surefit system. Plug and play. Modern, reliable and ice cold ac. Boom done.
 

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