Reverse lights come on in neutral (700r4) - The 1947 - Present Chevrolet & GMC Truck Message Board Network

mosel70 · 12-30-2018, 01:13 AM

'70 C10, originally a 4-speed manual, PO put in a TH400, I just put in a 700R4 with Lokar shift linkage and a new CPP steering column (column shifting). It has the standard neutral safety switch (NSS), got it all wired correctly. I adjusted the NSS all the way to one side and reverse lights come on in neutral. The passenger side mount screw hole is about half the hole off from lights coming on in reverse.
Any ideas out there?

btw, this forum was a big help helping me figure out the wiring since it was originally a manual. Thanks!

**Sheepdip** · 12-30-2018, 06:54 AM

If it's the standard factory NSS/Backup switch you may be hooked to the wrong side. I'd try switching the two connections unless you've already tried that.
You can test and adjust that switch with an ohm meter to get it spot on and prove that it is indeed working as it supposed to.

https://www.ididitinc.com/ft-3078-tech-tips.html#q33641

**special-K** · 12-30-2018, 09:16 AM

Sounds like the switch adjustment is off, if they only come on when in neutral right next to reverse.

mosel70 · 12-31-2018, 02:52 AM

Thanks gents for the replies. I'm certain I have the wiring right. I installed the switch and without the screws in I can get the b/u lights to go on and off by moving the switch. I just can't get them to go on in reverse, just when it finally gets to drive. I installed the switch from the old steering column, which is the same switch, and it's the same issue.
I had a 3-speed TH400 in it and now have a 4-speed w/od 700R4. Here's a pic of the switch. I'm going to call CPP tomorrow a.m., they made the column. I'm also calling Monster Transmission where I got the tranny. I'll let you know what they said.
Thanks again!

**special-K** · 12-31-2018, 09:16 AM

There are slots where it mounts to the column for adjustment.

kaycee · 12-31-2018, 09:31 AM

TURN ign. on DO NOT START put truck in R and loosen 2 screws then slide the switch until the lisghts come on ,tighten screws down and your done.

praisegeetarman · 12-31-2018, 11:46 AM

What mose170 states in his original post is that he has tried to adjust it. It's all the way to the end of the slots and still not right.
He wants to know if anyone has had this problem before.......

Andy4639 · 12-31-2018, 03:29 PM

Take it off and make sure the tab that the gear rod moves is in the right place. It could have been loose at some point and it went by it. Take it off and disconnect it and use a OHM meter to check it.

Make sure you have the wires correctly installed also.
The picture is reference only.

**randy.powell** · 01-01-2019, 10:21 AM

IIRC aren't there 2 different switches? One for powerglides and one for turbo's? Could be wrong but I think I've seen 2 different part numbers in the parts catalogs...

Randy

mosel70 · 03-01-2019, 07:01 PM

Well, here's the rest of the story. I called Brother's and CPP, both didn't have additional help to offer. I decided to try a Flaming River steering column, wow, what a difference in quality.
FR20030PL-F 1967-72 GMC Truck Column Shift Tilt Column with Neutral Safety Switch at 10" (3/4"-36 Shaft) - Polished Finish

Guess you get what you pay for (for almost 3x as much). NSS adjusted just fine, everything works. I found the NSS mount holes on the CPP column drilled off about 3/8". Column shaft diameter on both columns exactly the same. While I doing the column swap decided to also put in

- Steering Universal Joint, Standard, Steel, Polished, 3/4 in. 36-Spline, 3/4 in. DD, FR1715DDPL
- Steering Universal Joint, Standard, Steel, Polished, 1 in. DD, 3/4 in. 30-Spline, FR1746DDPL
- Steering Shaft, Power/Manual Steering, Steel Alloy, Natural, Double D, 42 3/4 in. Long, Universal, FR1856

Thanks everyone for the help!

12-30-2018, 01:13 AM	#1
mosel70 Registered User Join Date: Jul 2016 Location: Las Vegas, NV Posts: 116	Reverse lights come on in neutral (700r4) '70 C10, originally a 4-speed manual, PO put in a TH400, I just put in a 700R4 with Lokar shift linkage and a new CPP steering column (column shifting). It has the standard neutral safety switch (NSS), got it all wired correctly. I adjusted the NSS all the way to one side and reverse lights come on in neutral. The passenger side mount screw hole is about half the hole off from lights coming on in reverse. Any ideas out there? btw, this forum was a big help helping me figure out the wiring since it was originally a manual. Thanks! Last edited by mosel70; 12-30-2018 at 01:26 AM.

12-30-2018, 06:54 AM	#2
Sheepdip Senior Member Join Date: Nov 2018 Location: Waterford California Posts: 2,588	Re: Reverse lights come on in neutral (700r4) If it's the standard factory NSS/Backup switch you may be hooked to the wrong side. I'd try switching the two connections unless you've already tried that. You can test and adjust that switch with an ohm meter to get it spot on and prove that it is indeed working as it supposed to. https://www.ididitinc.com/ft-3078-tech-tips.html#q33641

12-30-2018, 09:16 AM	#3
special-K Special Order Join Date: Nov 2004 Location: Mt Airy, MD Posts: 85,852	Re: Reverse lights come on in neutral (700r4) Sounds like the switch adjustment is off, if they only come on when in neutral right next to reverse. __________________ "BUILDING A BETTER WAY TO SERVE THE USA"......67/72......"The New Breed" GMC '67 C1500 Wideside Super Custom SWB: 327/M22/3.42 posi.........."The '67" (project) GMC '72 K2500 Wideside Sierra Custom Camper: 350/TH350/4.10 Power-Lok..."The '72" (rolling) Tim "Don't call me a redneck. I'm a rough cut country gentleman" R.I.P. ~ East Side Low Life ~ El Jay ~ 72BLUZ ~ Fasteddie69 ~ Ron586 ~ 67ChevyRedneck ~ Grumpy Old Man ~

12-31-2018, 02:52 AM	#4
mosel70 Registered User Join Date: Jul 2016 Location: Las Vegas, NV Posts: 116	Re: Reverse lights come on in neutral (700r4) Thanks gents for the replies. I'm certain I have the wiring right. I installed the switch and without the screws in I can get the b/u lights to go on and off by moving the switch. I just can't get them to go on in reverse, just when it finally gets to drive. I installed the switch from the old steering column, which is the same switch, and it's the same issue. I had a 3-speed TH400 in it and now have a 4-speed w/od 700R4. Here's a pic of the switch. I'm going to call CPP tomorrow a.m., they made the column. I'm also calling Monster Transmission where I got the tranny. I'll let you know what they said. Thanks again! Attached Images

12-31-2018, 09:16 AM	#5
special-K Special Order Join Date: Nov 2004 Location: Mt Airy, MD Posts: 85,852	Re: Reverse lights come on in neutral (700r4) There are slots where it mounts to the column for adjustment. __________________ "BUILDING A BETTER WAY TO SERVE THE USA"......67/72......"The New Breed" GMC '67 C1500 Wideside Super Custom SWB: 327/M22/3.42 posi.........."The '67" (project) GMC '72 K2500 Wideside Sierra Custom Camper: 350/TH350/4.10 Power-Lok..."The '72" (rolling) Tim "Don't call me a redneck. I'm a rough cut country gentleman" R.I.P. ~ East Side Low Life ~ El Jay ~ 72BLUZ ~ Fasteddie69 ~ Ron586 ~ 67ChevyRedneck ~ Grumpy Old Man ~

12-31-2018, 09:31 AM	#6
kaycee Registered User Join Date: Jan 2000 Location: Wyoming USA Posts: 2,446	Re: Reverse lights come on in neutral (700r4) TURN ign. on DO NOT START put truck in R and loosen 2 screws then slide the switch until the lisghts come on ,tighten screws down and your done. __________________ 2001 Silverado K-1500 2005 FXDWG stage3 69 CHEVY Short/Step 327/4L60 373 posi 63 IMPALA 327

12-31-2018, 11:46 AM	#7
praisegeetarman Registered User Join Date: Feb 2010 Location: Harrah, Washington Posts: 323	Re: Reverse lights come on in neutral (700r4) What mose170 states in his original post is that he has tried to adjust it. It's all the way to the end of the slots and still not right. He wants to know if anyone has had this problem before....... __________________ 71 Blazer 4X4 (unmolested, all original (including paint) 74,000 mile barn find) 67 Camaro RS SS (unmolested, all original (including paint) 81,000 mile barn find) Keith Riel

12-31-2018, 03:29 PM	#8
Andy4639 Old member Join Date: Jan 2002 Location: Liberty, & Garden City S.C. , U.S. Posts: 19,945	Re: Reverse lights come on in neutral (700r4) Take it off and make sure the tab that the gear rod moves is in the right place. It could have been loose at some point and it went by it. Take it off and disconnect it and use a OHM meter to check it. Make sure you have the wires correctly installed also. The picture is reference only. __________________ 1971 LWB Custom, 6.0LS & 4L80E, Speedhut.com GPS speedometer & gauges with A/C. 20" Boss 338's Grey wheels 4 wheel disc brakes. My Driver Seeing the USA in a 71 Upstate SC GM Truck Club 2013,14 and 2016 Hot Rod Pour Tour http://upstategmtrucks.com/ Get out and drive the truck this summer and have some fun! It sucks not being able to hear! LWB trucks rule, if you don't think so measure your SWB! After talking to tech support at Air Lift I have found out that the kit I need is 60811. Per the measurements I gave them. Ride height of truck inside spring and inside diameter of springs.

01-01-2019, 10:21 AM	#9
randy.powell Senior Member Join Date: Jun 2014 Location: Bushwood, MD Posts: 510	Re: Reverse lights come on in neutral (700r4) IIRC aren't there 2 different switches? One for powerglides and one for turbo's? Could be wrong but I think I've seen 2 different part numbers in the parts catalogs... Randy

03-01-2019, 07:01 PM	#10
mosel70 Registered User Join Date: Jul 2016 Location: Las Vegas, NV Posts: 116	Re: Reverse lights come on in neutral (700r4) Well, here's the rest of the story. I called Brother's and CPP, both didn't have additional help to offer. I decided to try a Flaming River steering column, wow, what a difference in quality. FR20030PL-F 1967-72 GMC Truck Column Shift Tilt Column with Neutral Safety Switch at 10" (3/4"-36 Shaft) - Polished Finish Guess you get what you pay for (for almost 3x as much). NSS adjusted just fine, everything works. I found the NSS mount holes on the CPP column drilled off about 3/8". Column shaft diameter on both columns exactly the same. While I doing the column swap decided to also put in - Steering Universal Joint, Standard, Steel, Polished, 3/4 in. 36-Spline, 3/4 in. DD, FR1715DDPL - Steering Universal Joint, Standard, Steel, Polished, 1 in. DD, 3/4 in. 30-Spline, FR1746DDPL - Steering Shaft, Power/Manual Steering, Steel Alloy, Natural, Double D, 42 3/4 in. Long, Universal, FR1856 Thanks everyone for the help! Attached Images

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