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1968 Dodge Charger A/C 440 Heater Blower Not working

Davis Lewis

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Hi,
I am trying to make the blower/ heater fan turn on. I am getting battery voltage all the time at the plug in the engine bay that connects to the motor no matter what position the fan speed switch is in. I assume the fan speed switch sets the resistance in the circuit and when its in the off position I should get 0V at the plug? I found a wiring diagram but I have 4 wires (one is 3 pin connector and the other is a single pin connector)going to the heater resistor not 3 as shown in this diagram? I`m confused, a correct wiring diagram would be very helpful for me if I have the wrong one.

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My blower motor does not turn on so I am guessing there is high resistance somewhere in my circuit
 
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Take a look at this thread. Good wiring diagram and circuit path for each blower speed.

https://www.forbbodiesonly.com/mopa...rs-solution-to-the-unobtanium-problem.200988/

I jumpered 12V to the connector after the heater fan switch and I can run the fan at two different speeds. I also tested the switch and it seems to be working fine.

And ok this helps alot, thanks! But where does this "BATT" wire get 12V from? I am trying to trace my way back.

I do not have an A/C compressor attached to the engine btw

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Fan switch gets power from Tan wire in 6 wire pigtail that is connected to Heat/AC selector. Selector gets power from black wire in same harness. Also, the fan should run anytime any Heat/AC selector buttons are pushed, regardless of fan speed slider position. The item circled is the time delay relay, it provides power to the AC compressor for a few minutes when Heat or Defrost is selected. After a few minutes vacuum opens the delay relay contacts and the compressor shuts off, this is NOT needed for fan operation.
 
Fan switch gets power from Tan wire in 6 wire pigtail that is connected to Heat/AC selector. Selector gets power from black wire in same harness. Also, the fan should run anytime any Heat/AC selector buttons are pushed, regardless of fan speed slider position. The item circled is the time delay relay, it provides power to the AC compressor for a few minutes when Heat or Defrost is selected. After a few minutes vacuum opens the delay relay contacts and the compressor shuts off, this is NOT needed for fan operation.

Oh ok, so "14T" is connected to 12V or "14BK" when Heat or A/C button is pressed. "14BK" then gets its power from "C1-14BK*"? If so, the instrument panel connector is a single connection connector?

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14BK is the feed getting power from C1-14BK*. When a Heat/AC selector button is depressed 14T is powered from 14BK and feeds power to fan switch. Fan switch feeds blower resistor on different legs to provide mid and high speeds. 14BR at Heat/AC selector feeds blower resistor and delay relay (compressor)when heat/defrost button is pushed. Yes, C1-14BK* is a black wire w/white stripe that is a single connector, mine is very close to fuse box. In the first post you said you have 12 volts at the connector at the fan motor, if so, fan should run when plugged in. Not sure what you are trying to diagnose.
 
14BK is the feed getting power from C1-14BK*. When a Heat/AC selector button is depressed 14T is powered from 14BK and feeds power to fan switch. Fan switch feeds blower resistor on different legs to provide mid and high speeds. 14BR at Heat/AC selector feeds blower resistor and delay relay (compressor)when heat/defrost button is pushed. Yes, C1-14BK* is a black wire w/white stripe that is a single connector, mine is very close to fuse box. In the first post you said you have 12 volts at the connector at the fan motor, if so, fan should run when plugged in. Not sure what you are trying to diagnose.

Sounds good, I will try to find it! Well I get 12V at the connector of the fan motor when I unplug the motor. When I plug it in I get ~2V at the connector so the fan doesn`t spin.
 
But the fan runs when you jumped the two wires mentioned earlier?
Yes but I should have been clearer. I directly attached a 12V battery here to "LOW" and "HIGH" to make the fan spin at two different speeds.
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