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Old 01-29-2018, 09:04 PM   #1
BigMike56-72
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Neutral Safety Switch/Backup Lights

I already searched for the info I was looking for but didnt quite find it so I will ask here.

I recently replaced my steering column from non-tilt to tilt. In the process the NSS switch that came with my new column was different that was my truck had to begin with. I was told I could just replace the L shape plug with the one provided and all would be good. (Truck vs Van NSS) Well not so fast as I don't have backup lights when I put my truck in Reverse. My truck started off as a Std trans so I dont have the purple wires for the NSS which is fine since I'm the only who drives it but again the issue is my reverse lights don't come on.

Based on the pictures below I think I have it wired correctly but wanted to pick your brains to see if I did it right. Hopefully I just have the wires wrong and its a simple fix.

The light green wire goes to the right plug and the dark green to the left is what I am thinking??

Again thanks for all your help.
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Old 01-29-2018, 10:32 PM   #2
zicc1835
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Re: Neutral Safety Switch/Backup Lights

Subd,
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Old 01-29-2018, 11:02 PM   #3
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Re: Neutral Safety Switch/Backup Lights

use your ohm meter, put the truck in reverse (chock the wheels and set the emergency brake) and see which two tabs are connected electrically. This should be the dark and light green wires. then put the truck in neutral, and the other tabs should be connected electrically (switch closed). This should be for the purple and white wires. You may have to reterminate the ends. Learn to use an ohm meter it is your friend.
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Old 01-30-2018, 11:42 AM   #4
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Re: Neutral Safety Switch/Backup Lights

Also the reverse back up adjustment if very sensitive. what i did is shift the lever into reverse then adjust the switch on thee column until they light up then tighten the switch down. that is if you have it wired correctly.
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Old 01-30-2018, 07:53 PM   #5
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Re: Neutral Safety Switch/Backup Lights

Thanks for the tips. I will attempt to fix tonight.

Mike
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Old 02-03-2018, 11:17 AM   #6
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Re: Neutral Safety Switch/Backup Lights

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Originally Posted by Mr Chevorlet View Post
Also the reverse back up adjustment if very sensitive. what i did is shift the lever into reverse then adjust the switch on thee column until they light up then tighten the switch down. that is if you have it wired correctly.
Shouldn't the reverse lights come on even if they come on in the wrong position? I go from P-R-N-D-1-2 and I see no lights. I have changed up the wiring and tried both again and I still do get the reverse lights to come on. Does this sound like a bad NSS to you? It is brand new but we all know new stuff can come broken as well. Thanks again.
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Old 02-03-2018, 03:32 PM   #7
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Re: Neutral Safety Switch/Backup Lights

Put a jumper wire between the socket that attaches to the NSS. If the reverse lights do not come on you will need to check for power at the lamp sockets and at the switch to narrow down the problem.
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Old 02-03-2018, 06:45 PM   #8
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Re: Neutral Safety Switch/Backup Lights

Another approach is to make sure the switch is actually installed correctly on the tab that comes off of the steering column. Sometimes the tab from the column gets in front of the switch and pushes all the way to the right, bypassing the switch from actually being able to switch on/off.

Here's what I had success doing:
1. Plug in the harness to the NSS and turn key into on position without starting truck
2. Put into Reverse
3. Unscrew and remove the Neutral Safety Switch from the column. (two small screws)
4. Manually slide the switch (moves left and right) into the position that activates the reverse lights.
.....a. Make sure your bulbs are good.
.....b. Helps to have a second set of eyes as you slide the switch, but you can do it on your own too.
5. Lights come on (hopefully)
6. Reinstall NSS by lining up and placing slot on switch over the tab that comes up from the column.
7. Tighten up the screws.
8. Put her in park or take her out for a celebration ride.

Hope it's easy as that. Worked for me when replacing mine.

SIDENOTE: I did a swap from 3 on the tree to an automatic. 3 speed never had a working neutral cut off (purple wire if I recall). Truck can now start in any gear. I may cut the wire and harness to the NSS so it actually functions. I've read a few stories about members not doing the neutral safety, and starting up in gear and resulting in body damage.



Last edited by vinro; 02-03-2018 at 08:35 PM. Reason: ADDED PICTURE and trying to make the description as clear as I can
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Old 02-03-2018, 09:03 PM   #9
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Re: Neutral Safety Switch/Backup Lights

Vinro and Bonestock3ott,

Thank you so much for your help. I am going to try both suggestions and hopefully I will be good to go. I will keep you all posted.

Thanks

Mike

Last edited by BigMike56-72; 02-03-2018 at 09:03 PM. Reason: typo
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Old 02-03-2018, 09:45 PM   #10
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Re: Neutral Safety Switch/Backup Lights

So based on the pictures I posted above should either of the green wires have power going through them? I put the key in the ON position and put my test light on both wires and I don't see any power coming through them. If that is the case my problem is now with power and not the NSS correct?
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Old 02-04-2018, 02:57 PM   #11
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Re: Neutral Safety Switch/Backup Lights

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Originally Posted by BigMike56-72 View Post
So based on the pictures I posted above should either of the green wires have power going through them? I put the key in the ON position and put my test light on both wires and I don't see any power coming through them. If that is the case my problem is now with power and not the NSS correct?
Yes, one should have power with the key in the on position. If you don't have power, check your fuses. BTW, it doesn't matter which wire is on which terminal, it's just an on/off switch. So as long as you have them on the two terminals you show with arrows in your pic, you should be fine, the other two terminals are for the neutral safety switch.
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Old 02-04-2018, 03:20 PM   #12
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Re: Neutral Safety Switch/Backup Lights

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Old 02-04-2018, 03:42 PM   #13
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Re: Neutral Safety Switch/Backup Lights

You might check if you have proper ground. Here's a link with some alternative info...

http://67-72chevytrucks.com/vboard/s...hlight=reverse
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Old 02-04-2018, 04:25 PM   #14
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Re: Neutral Safety Switch/Backup Lights

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Originally Posted by ls1nova71 View Post
Yes, one should have power with the key in the on position. If you don't have power, check your fuses. BTW, it doesn't matter which wire is on which terminal, it's just an on/off switch. So as long as you have them on the two terminals you show with arrows in your pic, you should be fine, the other two terminals are for the neutral safety switch.
I just checked and I don't have power for either wire. I checked my fuses (top and bottom) and they are all good. I replaced both backup bulbs. I don't know why these wires don't have some sort of power if all the fuses are good. Are these wires powered somewhere else? From looking at the electrical drawings (if I am reading it right lol) looks like it makes a connection to the tail&stop lp/ harn. connector, which I dont know where to find.
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Old 02-04-2018, 05:01 PM   #15
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Re: Neutral Safety Switch/Backup Lights

Mike, if your test light is the style with a sharp point, pierce the wires before those butt connectors to check for power. This will help eliminate bad connections on those connections. I would also run a jumper from a 12 volt source to the side of the connector that feeds the lights to see if you get them to light that way.. If they do great than you can either decide to wire in a new power feed since the factory power feed is not working or track down the problem. If they do not light then you either have a broken wire, bad ground to fix.
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Old 02-04-2018, 05:08 PM   #16
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Re: Neutral Safety Switch/Backup Lights

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Originally Posted by BigMike56-72 View Post
I just checked and I don't have power for either wire. I checked my fuses (top and bottom) and they are all good. I replaced both backup bulbs. I don't know why these wires don't have some sort of power if all the fuses are good. Are these wires powered somewhere else? From looking at the electrical drawings (if I am reading it right lol) looks like it makes a connection to the tail&stop lp/ harn. connector, which I dont know where to find.

I can't enlarge the wiring diagram you posted, so I can't be certain you have the proper diagram for your truck.. Wiring in your truck could have been previously changed, cut, re-routed, etc.. As someone posted, a volt meter and/or test light is your friend..

If your truck is still wired correctly (unaltered), the dark green wire comes from the fuse box and carries power to the back up/NSS.. The light green wire goes to the back up lights..

The following is for testing purposes only, not meant to be a permanent installation. Make a jumper long enough to reach between a 12 volt power source and the light green wire plug.. Add a 5 - 7 amp fuse for safety if you want.. Locate a 12 volt power source and attach one end of the jumper to it.. Attach the other end of the jumper to the light green wire.. If the wiring and bulbs are good, the back-up lights should come on...If not, you have a break or disconnect between the plug and the bulbs..

When you get the back up lights working in this manner, remove the jumper from the light green wire and connect the plug to the back up/NSS.. Back probe the dark green wire with the jumper (still attached to a power source).. Put the shift lever in Park or Neutral and adjust the NSS until the back up lights come on.. Now all that left is to check and/or repair the dark green wire between the fuse box and the plug where it terminates at the NSS...
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Old 02-04-2018, 05:11 PM   #17
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Re: Neutral Safety Switch/Backup Lights

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Originally Posted by Bonestock3ott View Post
Mike, if your test light is the style with a sharp point, pierce the wires before those butt connectors to check for power. This will help eliminate bad connections on those connections. I would also run a jumper from a 12 volt source to the side of the connector that feeds the lights to see if you get them to light that way.. If they do great than you can either decide to wire in a new power feed since the factory power feed is not working or track down the problem. If they do not light then you either have a broken wire, bad ground to fix.
Excellent post Bonestock.. You posted while I was typing..
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Old 02-05-2018, 01:31 AM   #18
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Re: Neutral Safety Switch/Backup Lights

Thanks RustyPile and Bonestock for the help.

I was able to track why I didn't have power on the dark green wire. My fuse was popped. I replaced it and while I was hooking up a jumper wire to see if I could make the reverse lights come on I saw it pop. I replaced the fuse again and it popped. Pretty much whenever I connect the green wires the fuse pops. I took out the reverse lights and the housing to take a look at the wiring and it looks fine to me. I did notice that on the driver side wiring it had a ground wire clipped onto the same green wire as the light. It was grounded to the inside of the bed. Is that right? I tell ya these electrical bugs are a pain in the rear end. So pretty much I need to figure out what's causing the fuse to pop when the reverse light switch is engaged.

Mike
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Old 02-05-2018, 02:01 AM   #19
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Re: Neutral Safety Switch/Backup Lights

So I just tried hooking up 12V power from the fuse panel to the light green wire. I was able to see my passenger reverse light come on but faint. I noticed the wire was getting hot so I disconnected it. The driver side did not come on at all. So now, I know I have power to the dark green wire and somewhat connectivity to the passenger side reverse light. A few questions.


Should the wire have been getting hot like that?

Is it normal to have a ground wire spliced into the same light green cable that powers the driver side reverse light? This is the type of connector on the driver side reverse light. Doesn't seem right to me. Like I said it's spliced into the green wire and then the other wire is grounded to the truck.

Sorry for the the questions. As you can tell electrical issues and I don't get along.
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Old 02-05-2018, 03:24 AM   #20
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Re: Neutral Safety Switch/Backup Lights

Quote:
Originally Posted by BigMike56-72 View Post
So I just tried hooking up 12V power from the fuse panel to the light green wire. I was able to see my passenger reverse light come on but faint. I noticed the wire was getting hot so I disconnected it. The driver side did not come on at all. So now, I know I have power to the dark green wire and somewhat connectivity to the passenger side reverse light. A few questions.


Should the wire have been getting hot like that?

Is it normal to have a ground wire spliced into the same light green cable that powers the driver side reverse light? This is the type of connector on the driver side reverse light. Doesn't seem right to me. Like I said it's spliced into the green wire and then the other wire is grounded to the truck.

Sorry for the the questions. As you can tell electrical issues and I don't get along.
Neither green wire should have a jumper directly to ground.. Both these circuits (wires) are for carrying current to bulbs.. Disconnect that grounded jumper and then replace the fuse.. If the back up lights still don't work, (they probably will now work) follow the testing procedures I posted earlier..
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Old 02-05-2018, 03:47 AM   #21
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Re: Neutral Safety Switch/Backup Lights

I got rid of mine, it provides no service other than not being able to start my truck in gear.

I like not having it, has starting in gear with a turbo 350 is what I like!
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Old 02-05-2018, 12:51 PM   #22
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Re: Neutral Safety Switch/Backup Lights

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Originally Posted by RustyPile View Post
Neither green wire should have a jumper directly to ground.. Both these circuits (wires) are for carrying current to bulbs.. Disconnect that grounded jumper and then replace the fuse.. If the back up lights still don't work, (they probably will now work) follow the testing procedures I posted earlier..
RustyPile,

That was it. I disconnected that ground wire and now my backup lights come on nice and bright. Thank you so much! Now I need to adjust the NSS because the reverse lights come on when I shift to N and not R, but that should be simple to fix. Appreciate all the help with this.
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Old 02-05-2018, 12:59 PM   #23
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Re: Neutral Safety Switch/Backup Lights

If mounted, loosen the screws and slide that NSS clockwise toward passenger side a bit and the switch should line up for reverse.

Last edited by vinro; 02-05-2018 at 01:01 PM. Reason: Added detail
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Old 02-12-2018, 11:18 AM   #24
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Re: Neutral Safety Switch/Backup Lights

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If mounted, loosen the screws and slide that NSS clockwise toward passenger side a bit and the switch should line up for reverse.
All set. Thanks for all the great info. My truck is finally back on the road again.
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Old 11-17-2018, 02:19 PM   #25
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Re: Neutral Safety Switch/Backup Lights

Hi all, so for my stupid question of the day...what are the 2 wires (terminals) for on the reverse light switch on the column? My restore project didn't have reverse lights in the new replacement harness and I am now installing the circuit. I have ran a single line back to the tail lights to feed both right & left reverse lights, tail lights are grounded in the rear. But on this tread i see a light and dark green lead for the reverse lights does one of my offset terminals at the column for to ground? Please advise...
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