NYNick

Heater box and fan wires

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I'm rebuilding the car and have re-installed my rebuilt heater box. I put new wires on the fan, but forget where these wires (+ and -) go? I see no labeled wires in my harness in the engine bay, and am unsure if it hooks up inside the passenger compartment under the dash. I can't remember where these wires were, or where they go?

 

 Does anyone know off hand? Engine bay? Under dash? Maybe even pix?

 

74Tii BTW. 

 

Thanks

 

Nick

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The two wires from the fan connect to the resistor plate on the inside of the heater box.  The wires from the control lever connect to the outside of that plate as shown above.

Fan Motor Electrical Connections (1).jpg

Fan Motor Electrical Connections (2).jpg

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Just finishing up my box. Sooooo happy to have it done. My car is a 75, not sure if you have a early or late one.

365bf651d4f9a01f88ee0a546d406403.jpg
48e2ef167766cc82cc5530fb3b7216f8.jpg
c65a368269874614f200b0fb5546882c.jpg


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The electrical wires will be under the dash and plug into the side of the heater box as shown on several of the photos posted by othersh. Do you have the 3 speed pull knob (early) or the levers (late) for the fan?

Sent from my STH100-1 using Tapatalk

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2 hours ago, Guy Cocquyt said:

The electrical wires will be under the dash and plug into the side of the heater box as shown on several of the photos posted by othersh. Do you have the 3 speed pull knob (early) or the levers (late) for the fan?

Sent from my STH100-1 using Tapatalk
 

I have levers for the fan. Still go in the side of the heater box?

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1 hour ago, NYNick said:

I have levers for the fan. Still go in the side of the heater box?

 

The wires from the lever still connect to the spade connectors on the outside of the resistor plate/heater box.

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This means I have to pull the box, open it up and connect the fan wires to the resistor plate. Holy crap that sucks.

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FWIW here is the part that I did as well, just to make sure it doesn't have to come apart for a 3rd time.  The URL shows the rebuild tips. 

 

https://docs.google.com/document/d/1-3_4FJ7hItQufdT7piBrudjmfFfHuNw-sWANvmv9o7g/edit

 

 

Another thing I take care of is the cable that goes from the circuit board /resistor to the fan motor. The female connector that connects to the board usually breaks. They are made of brass, so this is a good time to cut off the old plug and splice in a new one. There are two methods that you can use to repair this:

  1. For the first method, cut the curved part of the connector completely and grind it to become a male spade connector, or solder a short pigtail with a female connector crimped at the end of the wire. I made a small hole in the connector and fed the pig tail through it before soldering it. After that, it should be a secure contact.

  2. The other method is to break the curved part of the connector and convert it into a male connector. This way, the blower harness male connector at the resistor end, need to be converted to female. Check both  inner and outer female spade of the blower resistor. Don’t forget to check and make sure the resistors are good.

 

Method A

IMG_7928.JPG9W1RqITkNrmsafj67bhGwqRxxLqZ6Rgwl245oSDihAmMQF0T7bu6Oy2prr3-BVhuc03suDA8StdEyu9nAmcI9xs0nqhK6eXu5gN23cEY3fk1MgJ2VQ5_Ct7pKMe3tALgy10JYlZW


 

Method B

IMG_7930.JPG

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20 hours ago, Dudeland said:

One more541f008533ee1ea78dadfdb8514f828a.jpg3c5af11bef2ea1dcdfe1e6a86ed8be27.jpg


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This is awesome. After beating myself to death taking the box out again today, opening it and re-routing the fan wires to the resistor inside the box and  then getting ready to reinstall, I have a question on this picture. 

 

Here we see back of the resistor box, and three connections, I think. I also have a yellow, purple and black wire, as well as a green wire also coming from the levers.

 

So....black to +, purple to 2/3 and yellow to 1/3? Please verify.

 

Also, where does the green wire with the male spade go? 

 

Thanks guys and Guy!

 

Nick

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On 10/24/2018 at 7:44 PM, Dudeland said:

One more541f008533ee1ea78dadfdb8514f828a.jpg3c5af11bef2ea1dcdfe1e6a86ed8be27.jpg


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Dude, Hal or others?

 

Could you verify/specify which colored wire goes where? In one picture it looks like black goes to positive and yellow goes to 1/3, but in another it looks like yellow goes to positive.

 

Thx

 

Nick

22 hours ago, halboyles said:

 

The wires from the lever still connect to the spade connectors on the outside of the resistor plate/heater box.

Thx Hal.

 

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