Neutral safety switch

[DetMatt1]

My question is how is the wiring routed from the bulkhead to the switch? Does it go over to the passenger side and loop back over the top of the trans? I have a long harness with a short distance and I don't remember from when I took it apart.

 

[71Plym]

Does it go over to the passenger side and loop back over the top of the trans?

Yes, that is how I recall it was on my 71.

 

[Mopars & Missiles]

Matt, I agree with 71Plym, I think it goes towards the passenger side first then back over the top to the drivers side. There are a couple of wire harness clips that it goes into IIRC, one on pass side top of bellhousing and the other on the drivers side lower part of the case near the NSS. Here's a photo of how I 'think' it goes with a hand drawn black cable in the general area. You can see the clips on the trans. I believe it was routed this way to keep the cable away from the exhaust??

 

[DetMatt1]

Thanks guys! That helps.

 

[Chryco Psycho]

it will attach to the fire wall tabs over to where the regulator is mounted then drops down the tunnel there should be another tab where the extension housing bolts on & over to the NSS

 

[Mad Cuda]

Great information! I have a 1970 383 4 speed which the previous owner converted from a 318 3 speed. My reserve lights don't work so Im changing out the harness and NSS in hopes to fix them. I've not hooked up the harness yet, but when I unscrewed the old NSS, gear tranny oil came flowing out. Not sure if I need to drain tranny gear oil first or if the previous owner overfilled it, which is not usually possible on a manual tranny. I'm baffled. Any assistance would be appreciated.

 

[moparlee]

On a 4 spd the switch is called a back up light switch. It is below the gear oil fill plug so you will need to drain out some gear oil first. Or just be quick about removing and installing the switch, then top off the gear oil. While you are at check the speedo gear to make sure you have got the correct one for your gear ratio and tire diameter.

 

[Mad Cuda]

Thanks for the correct definition of the switch. Im a novice at this and learning a lot from guys like you. Didn't know it was normal to have the switch in contact with the gear oil. I'll proceed per your instructions. The speedo seems to be running ok. I unscrewed the retaining nut and inspected the cable. How do I check the speedo gear to make sure I have the right one? Thanks a lot for your assistance.

 

[Mad Cuda]

I forgot to mention that the switch that is installed now looks new and has two flat prongs. The new one I ordered, along with the harness, has three round connecting prongs. Not sure which one is correct for the 1970 383 4 Speed, but thought I would try the three prong I ordered online. Any input with be greatly appreciated.

 

[moparlee]

I forgot to mention that the switch that is installed now looks new and has two flat prongs. The new one I ordered, along with the harness, has three round connecting prongs. Not sure which one is correct for the 1970 383 4 Speed, but thought I would try the three prong I ordered online. Any input with be greatly appreciated.

The two flat prong switch is the correct one for the 4 spd, the one with the three round prongs is for the auto trans. If you look at the ends that go into the trans, they are also different. Talk to who ever you bought the switch and harness from and see if you can get the correct ones. Maybe just get the harness for now if the existing switch looks new. Someone here can probably tell you how to do a meter check of the switch and harness to see which one is faulty.

 

[moparlee]

Thanks for the correct definition of the switch. Im a novice at this and learning a lot from guys like you. Didn't know it was normal to have the switch in contact with the gear oil. I'll proceed per your instructions. The speedo seems to be running ok. I unscrewed the retaining nut and inspected the cable. How do I check the speedo gear to make sure I have the right one? Thanks a lot for your assistance.

Here is chart for the correct speedo gear size. You will need to pull the gear to see what the number of teeth is marked on the plastic gear. When you re-install, make sure the housing is clocked in the right position which also has the number of teeth (in a range) marked on it.

Mopar Speedometer Gear Selection Guide - MyMopar.com

 

[Mad Cuda]

After researching a little further, I found out that I purchased the wrong harness and switch. I'll send them back and get the correct ones. Testing the existing switch can safe me from purchasing a new one. Great information on the speedo gear!! Thanks a lot for your time and information. I'll follow your recommendations and see what happens. Thanks a lot!!