Many of you may remember the difficulty I had getting my 74 Dart started after restoring it. I finally broke down and took it to a mechanic who kept it two weeks and finally got it running. Prior to taking it to him, the reverse lights worked. After bringing it home, the reverse lights do not work.

I just learned that the mechanic changed the neutral safety switch when he had my car. The car has an automatic transmission, column shift and the old neutral safety switch was the original from 1974 when I bought the car. It kept falling off, therefore it needed replacing.

Q. 1 - Could the new switch be the reason the reverse lights do not work?
Q. 2 - How would I test to find the problem? I have a multimeter.

All bulbs in the brake lights and reverse lights are new. Brake lights, turn signals, and flashers work fine.

These lights have nothing to do with the brake lights, and blinkers. It is basically one hot wire to the switch, and from the switch one wire to the back of the car where it splits off to feed both lights than to ground.

Easy stuff first:

First, check if the switch is adjusted so that when in "R" it is activated. It is an odd little switch as it travels with the shifter, but only turns on the lights in one position out of several. Remember that the ignition switch has to be in the on position for these lights on work.

Second, check that the wire from the un energized side of the switch back to the lights has continuity, in other words wire not broken, or a bad connection. You can do this by touching VOM probe to where the wire connects to the switch, and the other probe to ground. Use the OHM scale there should be little resistance if the circuit is good. High resistance if it is open. Than check from the hot side of the switch back to its source of energy for continuity by checking for 12 volts. Place one probe on hot wire, and second probe to ground, should read 12 volts. If you have a test light, you may find this device to be easer to use.

Check for burned out bulbs & correct bulbs, this is probably not the problem because one of them should work out of two. Check to make sure you have a good ground at both lamp holders by touching you VOM probe on the side of the socket, and grounding the other prob. If no ground you will have to loosen the bolts holding the lamp and retighten them to make a good connection to ground.

I had a problem with my back up lights not working. My car has buckets and a floor shifted automatic, the switch is located at the shifter. From the switch there is a special jumper harness extender that patches into the circuit that runs to the column shifter wire that you have in your car. Turned out the one of the factory spade connectors was loose & corroded in the jumper behind the passenger side kick panel. Oh yeah, it was in the last place I looked...

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67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

I also have a '74 Dart Sport, and I don't recall this "switch" you are referring to. Where is it located? The only switch I remember dealing with was the neutral safety/back-up light switch located in the transmission housing.

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There's a difference between ignorance and stupidity.
Ignorance is not knowing any better.
Stupidity is knowing, yet doing it anyway.

WJA, you're describing a 1965-'69 reverse light switch. The car in question is a '74 and doesn't have one of those.

The '69-up cars have a combination neutral safety/reverse light switch screwed into the transmission. It has three pins on it. The centre pin is the neutral safety function; it is grounded when the transmission is in Park or Neutral. The outer two pins are the reverse light function; there's continuity between them when the transmission is in Reverse. There's a 3-wire socket that connects to this switch.

It sounds like the "mechanic" might've used the wrong new switch, or used a defective new switch, or damaged some wires or the socket when he was foolin' around under there. You might have someone check to see if the reverse lights blink on briefly as you slowly move the shifter from Park through to Drive with the ignition switch in the on position. If they blink on at all, but don't stay on, then there's a problem with the interface between the transmission shift selector "rooster comb" and the combination switch. Another quick test: unbend a paper clip and use it to connect the two outer holes in the 3-wire socket. Wrap a towel or something around the exposed paper clip so it won't ground out, turn the ignition on, and see if the reverse lights come on. If not, then there's a problem in the wiring.

You, ah, did check the fuse, right?

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Dan: Oooh yeah, forgot about the new stuff, sorrry. Do as Dan recomended.

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67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

I crawled under the car tonight and noticed the connector was the original connector that has been on the car since 1974 and was the same connector on it prior to taking it to the mechanic. I pulled it off the neutral safety switch and immediately noticed the switch was different. So I grabbed the detailed invoice from the mechanic and there was a charge on the bill for a new neutral safety switch. Prior to taking it to the mechanic, I replugged that connector so many times, I was really beginning to think about gluing the damn thing on, so it wouldn't fall off again.

As Dan suggested above, I took a paper clip, unbent it, and put each end in the outer two ends of the three prong female connector. I turned the ignition to ON, and put the car in reverse. The backup lights came on! So obviously my problem must be the new neutral switch is bad or the wrong one for my car.

I think I'll visit Advance Auto tomorrow. Did they make different kinds of switches for 74 Darts? If I remove the faulty switch, will transmission fluid leak out?

I had a similar problem that I finally traced back to the washer that makes contact with the transmission case. The new one was some sort of plastic and the old one was metal and a little more curved. I swapped out the washer and problem solved....I think it was the shape that allowed the little button on the switch to move to it's full on/off position thus activating the reverse lights.

Worth a look.

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Arizona Duster in Canada

There's only one kind of neutral safety/reverse light switch for a '74 — who knows what that "mechanic" installed! :shrug: You can prevent most of a fluid leak by jacking up the left front corner of the car so the fluid runs rearward/rightward before you unscrew the switch.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.