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Daniel Moreno

Dodgedartdan
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I have a 1975 dodge dart sport with a 72, 340 motor that I installed. I converted it from an automatic on the column to a four-speed with a used steering column that I bought at Carlisle. I set up everything to the best of my knowledge, but have no power when I turn the key. All my lights work. I do not have a neutral safety switch and I’m not sure if I need one? There is one connector from the harness under the instrumentation cluster that has 12 Volts of power? There’s also a connector from my transmission. See pictures. Any ideas besides recruiting paid help? Thanks so much. Dan M

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Lots of extra wires and interlocks as compared to 67 dart.

But the typical way a NSS works is when the trans is in park or neutral (neutral on a manual) the NSS provides a path to ground for the starter relay. Without that path to ground the relay can not engage and the starter will not spin.


You can do a few tests,

One is with the key in the run position is there 12v to one side of the ballast resister, 6 to 10v to the other side.

Second with the key in the start position is there 12v to both sides of the ballast resister.


Another is when the key is in the start position is there 12v to the "I" pin of the starter relay.

The "G" pin should be grounded when trans is in park or neutral. Open when in any other gear.

Screenshot_20230102-091716.png


Screenshot_20230102-101700.png

I'm not too familiar with the later cars, and there may be other interlocks like, seatbelt, etc. that interrupt the starter relay path from either the power side or the ground side.
 
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Then you have bigger problems.

You will need to trace out the path from the battery through the bulkhead connector to the ignition switch to the ballast resister.

And see where the power gets interupred.
 
The extra 2 pin connector in the second pic is where the start/run power comes from IIRC. I recently had to change the column in my 75 Dart Sport, put one from a 74 in it, and had to splice those 2 wires in to the harness to make it run. Look for the same size and color wires from the harness. Hope that helps,
 
The one on the transmission is for reverse lights, a neutral safety switch, if equipped, would likely be on the clutch pedal.
 
Hey missing linc, I think we might be on to something. There is definitely 12 volts dc from the connector in the 2nd photo. I should splice them to the 2nd and 5th wire (from left to right) on this steering wheel connector ?

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Daniel Moreno said:
Hey missing linc, I think we might be on to something. There is definitely 12 volts dc from the connector in the 2nd photo. I should splice them to the 2nd and 5th wire (from left to right) on this steering wheel connector ?

View attachment 1716029746
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If I remember right, that is correct. As long as the gauge and color are the same, you should be good.
 
I’m going do a little more preparation work like add engine oil and antifreeze, and give it a shot. No matter what. Thank you so much. I’ll definitely let you know. Dan from Connecticut
 
missing linc said:
As long as the gauge and color are the same, you should be good
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Not so fast there....
Color does not always match up.

Trace out the BLK by the red dot and see it go to a RED wire.

Screenshot_20230102-102941.png

You need to understand where the wires go to and come from. Randomly splicing wires together is a recipe for disaster.


I'm not saying that what Missing linc said is not correct. Just be sure before you start cutting and splicing
 
Dana67Dart said:
Not so fast there....
Color does not always match up.

Trace out the BLK by the red dot and see it go to a RED wire.

View attachment 1716029750
You need to understand where the wires go to and come from. Randomly splicing wires together is a recipe for disaster.


I'm not saying that what missing lnk said is not correct. Just be sure before you start cutting and splicing
Click to expand...
I agree, but when I did mine last summer, that was what worked, though I probably did consult a wiring diagram.
 
Daniel Moreno said:
I have a 1975 dodge dart sport with a 72,
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The engine year in this case is not too important.
1975 wiring has some unique circuit arrangements.
One important option that is critical to know is whether the car was originally equiped with a defrost grid for the rear window. Those cars came with a heavy duty alternator and battery wiring arrangement. One clue will be the rear window itself and/or the switch to turn it on. The other clue will be a grommet in the firewall with some large wires.

Dana67Dart said:
Not so fast there....
Color does not always match up.
Click to expand...
Exactly.
A pdf of the '75 valiant/dart wiring diagram from a service manual in this post.

Here's the general concept for the main power feeds.
A1 is Battery feed.
R6 is alternator feed.
1672688118410.png

With the key off, everything connected to the battery positive is still hot. Take your finger and follow the wires from the battery positive. The ammeter is just another section of the line. Nothing magical happens there, its two studs and a big metal plate that electricity can flow through in either direction. The color change is so the hookup is correctly done. That way the needle will point the correct way when the battery is discharging or charging.

Some '75 model year cars still got the '74 seatbelt interlock.
Hopefully your does not have that, but if it does, then it must be dealt with.

Daniel Moreno said:
Dana67dart, I’ve got no voltage to either side of the ballast with the key in the run position.
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J1 is the power feed to the key switch. If the large wire (red with white stripe) to the column connector is hot, then there ought to be power to the headlights, brake lights and dome lights.

Key in accessory positio n, there should be power for turn signals, heater fan, etc.
Key in run, should have provided power to the blue or blue and white wires at the ballast resistor.
 
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Looking at the 75 wiring diagram.

I realize how smart my dad was.

"The parts you don't add, don't cause you no trouble"

My 67 is just so simple. And it has lasted for 8 years longer than any 75!

And no one has died or been mamed for lack of all the "safey" add ons.
 
As best we can tell, this '75 was standard alternator wiring.
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The grommets in the firewall here do not have heavy red and black wires seen in the previous post.


Wire S4 is the safety switch.
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fold the ground prong on the starter relay ove and solder it to the side of the relay. Basically what they did int the 60's

s-l1600.jpg
 
In post 1 you're pointing at a separate connector with a red and black wire. Is this connector coming from the steering column or the main under dash harness?
 
The ignition switch wiring from the replacement column has a different connector than yours. That column ignition switch came from a 70-74 car. You need the 1975 switch. This difference can be seen by searching eBay : 75 valiant nos ignition switch. If you don't want to replace the switch, splice the red and black wires from the ignition switch connector to the red and black wires from the under dash main harness.
 
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