When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I have recently converted my 1972 F250 from a manual transmission with manual steering to a power steering and automatic transmission setup. Everything has been working fine until I realized that it does not have any wiring for the neutral safety switch since the manual transmission does not have one. I have tried searching schematics and wiring instructions but I have not found anything for my situation. Any advice or suggestions you have would be greatly appreciated! Thanks in advance.
Here is a good thread that talks about the neutral safety switch with some pictures. Your truck should have a bi-pass wiring connector in your under dash wiring harness. Here is a picture of what it looks like. The neutral safety switch wiring plugs in that location. Neutral safety switch don't work now? - The FORDification.com Forums
I have recently converted my 1972 F250 from a manual transmission with manual steering to a power steering and automatic transmission setup. Everything has been working fine until I realized that it does not have any wiring for the neutral safety switch since the manual transmission does not have one. I have tried searching schematics and wiring instructions but I have not found anything for my situation. Any advice or suggestions you have would be greatly appreciated! Thanks in advance.
First thing you need to do is say what engine and what transmission and where they came from.
All the neutral safety switch does is break the connection between the ignition switch and the "S" terminal on the start relay. If your column has the NSS on it all you have to do is locate the wire going to the "S" terminal and run it thru the NSS.
That said all this only works if you used a transmission from a truck with the correct manual lever on it and the shift linkage from a truck. The biggest mistake people make is installing a transmission from a car or truck that doesn't have the correct manual lever in it. In that case the stars won't line up.
Here is a good thread that talks about the neutral safety switch with some pictures. Your truck should have a bi-pass wiring connector in your under dash wiring harness. Here is a picture of what it looks like. The neutral safety switch wiring plugs in that location. Neutral safety switch don't work now? - The FORDification.com Forums
Great thanks for the information! I will take a look at that today!
The factory N/S switch would have been on the steering column, under the dash. My column was damaged and I couldn't use that style switch. Since my truck has a later trans, it had the provision for a N/S switch on the side of the trans. I used a switch from what I think was a late 70s E150 which came with a long lead which reached the harness under the dash.
I have this dangling from my steering column. Not sure of the history but I’m guessing someone switched out the steering column for a power steering addition. Only reason I haven’t tucked it away is because on cold mornings I often have to give it a light tap with the side of my foot in order to start her up.
I did not get it figured out as I was not able to find that bypass wiring in the under-dash wiring harness. The picture you attached earlier was very helpful but I was not able to find it anywhere. I have to remove the instrument cluster in a few days so I will look again once I do that. My biggest concern is making sure that the backup lights are working as it appears that is connected to the neutral safety switch wiring.
Last edited by Jacksanchez4351; Aug 1, 2024 at 05:50 PM.
I did not get it figured out as I was not able to find that bypass wiring in the under-dash wiring harness. The picture you attached earlier was very helpful but I was not able to find it anywhere. I have to remove the instrument cluster in a few days so I will look again once I do that. My biggest concern is making sure that the backup lights are working as it appears that is connected to the neutral safety switch wiring.
You don't have to remove the cluster for this, as everything is located on the top of the steering column, roughly right above your ankles. If you can't see up there (lack of light), you should be able to at least feel for it. There should be a small lever or bar sticking out of the top of the steering column that moves back and forth (L & R) when you move the shift lever, and the NSS is spring loaded to ride up against it.
You don't have to remove the cluster for this, as everything is located on the top of the steering column, roughly right above your ankles. If you can't see up there (lack of light), you should be able to at least feel for it. There should be a small lever or bar sticking out of the top of the steering column that moves back and forth (L & R) when you move the shift lever, and the NSS is spring loaded to ride up against it.
I’m still new to this truck, but if he had a manual converted to automatic, he’s not going to have any of that (switch assembly sticking out of the steering column). I thought the reverse lights were triggered by a switch at the transmission in the manual models.
Again I may be wrong but I thought manual models didn’t have that switch.
I’m still new to this truck, but if he had a manual converted to automatic, he’s not going to have any of that (switch assembly sticking out of the steering column). I thought the reverse lights were triggered by a switch at the transmission in the manual models.
Again I may be wrong but I thought manual models didn’t have that switch.
I'm slapping myself upside the head a bit here, as somehow I thought your response in reply #7 was from the OP!
But all may not be lost, as who knows? Perhaps the truck originally had an automatic...or the steering column was swapped....
Your help has been so great! I have fixed the neutral safety switch portion but the backup lights are not working. I know that wiring is associated with the NSS but it didn’t fix that issue. With it going from manual to auto I’m not sure what else needs to be done. Any help is appreciated!