Need Help On How To Bypass The Nss

I want to bypass the NSS so I can pull the codes from my computer the NSS is not hooked up on my T5. Would I simply unplug the clear plug next to the starter safety plug and leave it oof the clutch switch and then unplug the other switch near the gas pedal and put a fuse or jumper plug?
I I a few plugs pictured below as reference they were cut off a car in the junk yard (they are not cut from my car).
 

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Code 67
Revised 18-Mar-2017 to include warning about the necessity of having a 5 speed O2 Sensor wiring harness when bypassing the wiring for test purposes

Cause of problem:
Clutch not depressed (5 speed) or car not in neutral (5 speed and auto) or not in park (auto) or A/C in On position when codes where dumped. Possible neutral safety switch or wiring problem. This code will prevent you from running the Key On Engine On tests.

External evidence from other sources claims that a code 67 can cause an idle surge condition. Do try to find and fix any issues with the switch and wiring if you get a code 67.

What the NSS (Neutral Safety Switch) does:
5 speed transmission: It has no connection with the starter, and the engine can be cranked without it being connected.
Auto transmission: It is the safety interlock that prevents the starter from cranking the engine with the transmission in gear.
What it does for both 5 speed and auto transmission cars:
The computer wants to make sure the A/C is off due to the added load on the engine for the engine running computer diagnostic tests. It also checks to see that the transmission is in Neutral (5 speed and auto transmission) and the clutch depressed (T5, T56, Tremec 3550 & TKO)). This prevents the diagnostics from being run when the car is driven. Key On Engine Running test mode takes the throttle control away from the driver for several tests. This could prove hazardous if the computer was jumpered into test mode and then driven.

The following is for 5 speed cars only. Do not do this unless you are sure that you have a 5 speed O2 Sensor harness!!!! Smoke, sparks and expensive pain in the wallet may ensue if you don’t.
The NSS code 67 can be bypassed for testing. You will need to temporarily ground computer pin 30 to the chassis. Computer pin 30 uses a Lt blue/yellow wire. Remove the passenger side kick panel and then remove the plastic cover from the computer wiring connector. Use a safety pin to probe the connector from the rear. Jumper the safety pin to the ground near the computer.
Be sure to remove the jumper BEFORE attempting to drive the car!!!

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It's actually the NGS. Nuetral Gear start circuit.

It's wired in parallel between the clutch pedal switch, and the sensor on top of the t-5. Only one has to be closed to tell the ECU you are in neutral, which will affect idle strategy.

To bypass it, just take the plug off the clutch switch, and stick a 5A blade fuse in there. This tells the ECU you are always in neutral and prevents some idle issues such as hanging idle. as well as the ability to run codes.

BTW, if you are doing this only to allow you to continue reading codes, just run the test with the clutch pedal pressed in the entire time.

You'll want to either connect up the NGS on the T-5 or, bypass it with the fuse to prevent hanging idle issues. What's the reason it's not connected on the t5? AOD-to-T5 swap?
 
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It's actually the NGS. Nuetral Gear start circuit.

It's wired in parallel between the clutch pedal switch, and the sensor on top of the t-5. Only one has to be closed to tell the ECU you are in neutral, which will affect idle strategy.

To bypass it, just take the plug off the clutch switch, and stick a 5A blade fuse in there. This tells the ECU you are always in neutral and prevents some idle issues such as hanging idle. as well as the ability to run codes.

BTW, if you are doing this only to allow you to continue reading codes, just run the test with the clutch pedal pressed in the entire time.

You'll want to either connect up the NGS on the T-5 or, bypass it with the fuse to prevent hanging idle issues. What's the reason it's not connected on the t5? AOD-to-T5 swap?


Is it the clear plug next to the starter safety plug that i pull out and put a 5amp fuse?

And yes originally this car was automatic I did a T5 swap the transmission that I bought was a remanufactured T5 and what they did was leave the NSG plug out they actually just put a bolt in there so until I can get up underneath and put the NGS switch back in there (which I have) I want to do this so that it's bypassed temporarily.
 
Is it the clear plug next to the starter safety plug that i pull out and put a 5amp fuse?

And yes originally this car was automatic I did a T5 swap the transmission that I bought was a remanufactured T5 and what they did was leave the NSG plug out they actually just put a bolt in there so until I can get up underneath and put the NGS switch back in there (which I have) I want to do this so that it's bypassed temporarily.

Yes. It's the clear one. Stick a fuse in there and it's bypassed.

The grey one is for the starter. You should leave that connected. The pic you show with the jumper is from an AOD car as the jumper was used to bypass it on the AOD's.

On the AOD's, the transmission harness lacks the provision for the NGS under the car. It's just not present on the harness, so there's nothing to plug the NGS in on the T5. To fix this, you need to replace the entire trans harness with one from a 5-spd that has the plug. This is the harness that the VSS, reverse lights and NGS plug into that runs through the trans tunnel wall, under the driver's seat, and to the pass kick panel area where it plugs into an 8-wire connector.

This entire harness will need to be changed before you go through the work of adding the NGS to the t-5 and trying to plug it in.
 
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Thank you Mustang5L5 you are absolutely right I have the other wire harness with me I also pulled one out of an automatic to see the difference and yes there is a difference in plugs. Right now my reverse lights do work with the automatic plug but I do plan on changing that once I resolve the issue I'm having with the car now. I do have a question the plug that has the gray clip by the gas pedal that was originally jumped is that for cruise control? It has a black wire with a gray clip that plugs into the other gray clip what a set of red wires that was originally jumped.
 
Read the last paragraph of my previous post. The answer is in there...


Sorry Jrichker you're right I see what you're talking about at first I thought you were talking about if I had a code 67 and how to eliminate that also I didn't want to go that route with grounding pin number 30 from the computer a bit touchy for me. I don't have the sensor in the transmission it was removed prior it is a remanufactured T5. But thanks again for your advice.
 
Thank you Mustang5L5 you are absolutely right I have the other wire harness with me I also pulled one out of an automatic to see the difference and yes there is a difference in plugs. Right now my reverse lights do work with the automatic plug but I do plan on changing that once I resolve the issue I'm having with the car now. I do have a question the plug that has the gray clip by the gas pedal that was originally jumped is that for cruise control? It has a black wire with a gray clip that plugs into the other gray clip what a set of red wires that was originally jumped.


That plug is the starter circuit. Remove the jumper and plug it into the clutch pedal switch. That will cause the car to only start with the clutch pedal depressed. It's jumped out on the AOD cars because there is no clutch
 
That plug is the starter circuit. Remove the jumper and plug it into the clutch pedal switch. That will cause the car to only start with the clutch pedal depressed. It's jumped out on the AOD cars because there is no clutch

I know about the starter safety kill plug,
thank you the plug in that picture I only use for reference that was on the side near the gas pedal by the center console I'll attach a picture to it to show you. I'm curious what this one goes to?
Because originally there was an open loop plug on that just like there was an open loop plug on the starter safety switch.
 

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I believe that is related to the cruise control and disables it when brake/clutch is depressed. Not 100% due to my car being a non-cruise car so I don't have that wiring.
 
I believe that is related to the cruise control and disables it when brake/clutch is depressed. Not 100% due to my car being a non-cruise car so I don't have that wiring.


I think you might be right because originally this was an aod that I converted to manual and the starter safety switch had a open loop connector that I removed and this switch had an open loop connector plug that I disconnected that's the only thing that I can think of that this switch goes to. Thanks again Mustang5L5 I really appreciate all your help.
 
It's actually the NGS. Nuetral Gear start circuit.

It's wired in parallel between the clutch pedal switch, and the sensor on top of the t-5. Only one has to be closed to tell the ECU you are in neutral, which will affect idle strategy.

To bypass it, just take the plug off the clutch switch, and stick a 5A blade fuse in there. This tells the ECU you are always in neutral and prevents some idle issues such as hanging idle. as well as the ability to run codes.

BTW, if you are doing this only to allow you to continue reading codes, just run the test with the clutch pedal pressed in the entire time.

You'll want to either connect up the NGS on the T-5 or, bypass it with the fuse to prevent hanging idle issues. What's the reason it's not connected on the t5? AOD-to-T5 swap?


To answer the question Yes this was a t5 swap but the reason I'm doing this is because the t5 does not have the NGS switch at all which I thought was weird my 88 does and it orginally a 5 speed Cali car!


*By putting the 5amp fuse in the clear plug this will still bypass the NGS letting the ECU know its in neutral right?
 
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To answer the question Yes this was a t5 swap but the reason I'm doing this is because the t5 does not have the NGS switch at all which I thought was weird my 88 does and it orginally a 5 speed Cali car!


*By putting the 5amp fuse in the clear plug this will still bypass the NGS letting the ECU know its in neutral right?


Yes. The ECU will always think it's in nuetral. Eventually you might want to get it wired up correctly so it's no longer bypasses and working like factory stock should
 
Yes. The ECU will always think it's in nuetral. Eventually you might want to get it wired up correctly so it's no longer bypasses and working like factory stock should


The one I'm concerned with is the one we think might go to the cruise control, I took a picture for reference below, orginally this one was jumped in addition to the started, that one I'll leave plunged in the safety clutch switch, but the clear one was tucked in the wiring harness and looked like it was factory that way. I also went to a salvage yard that had some foxbodys and the ones that were automatic 5.0 were done the same way. So my question is should unplug it and put the jumper back in in addition to putting the 5amp in the clear plug?
I just really wish I knew that plug goes to.

When I did the t5 swap I paid close attention to what wires were jumped and what was left unplug and orginally like you said the starter safety was jumped the clear plug that I'm going to put the 5amp fuse in was unplugged and the one I'm really curious about was jumped as well.

Just an FYI I did look on the clutch pedal and there is a switch near the gas pedal but still located on the clutch bracket and when the clutch is depressed that switch releases, there is a two black wires going into a great plug I'll take one more picture just for reference.
 

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**UPDATE**
Okay so I deleted the last post I didn't want this to keep going on about the same thing so I did a little bit more research and finally was able to work on my car today to see exactly what was going on. I still don't know exactly what the plug pictured below does but for now I put the jumper back on it (as it was orginally) and I plugged up with a jumper the starter safety (only temporary) I unplugged the clear plug just to do a test instead of putting a 5amp fuse in it (I will out a fuse in it later in just testing a few things now). When I got in the car and started driving it around it did good for a little bit but then as I slow down it wanted to come to a stall? It would idle at 800 rpm (keep in mind im running a Paxon 1220 supercharger. When the drops below a 1000 RPM it would fluctuate in idle then stall.I was able to make it back home and noticed that every time it falls below 1000 RPM it wants to stall so the good thing is every time I depress the clutch the car does not stall that is why I put the jumpers back on the plugs that were originally on there and unplug the clear plug just as a test to see what would happen and so far it didn't want to stall by pushing in the clutch. Keep in mind that this was an aod swap this T5 transmission is an aftermarket transmission it does not have the NSS switch inside the transmission must have came off a newer Mustang Lesson learned when buying an aftermarket transmission do your research. So moving on I idled up the idle to 1100 RPM and had no problems whatsoever I was able to drive the car continuously without it stalling it did want to drop down just below a thousand at sometimes but maintained a steady idle at 1100 where I had it set. So I'm going to do some more test I believe the culprit is in the throttle position sensor I found a good article by Jrichker that I'm going to read and test when I find the problem I will post up the results hopefully this will help someone else thanks again MustangL5L I appreciate all your help.
 

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**UPDATE**
Okay so I deleted the last post I didn't want this to keep going on about the same thing so I did a little bit more research and finally was able to work on my car today to see exactly what was going on. I still don't know exactly what the plug pictured below does but for now I put the jumper back on it (as it was orginally) and I plugged up with a jumper the starter safety (only temporary) I unplugged the clear plug just to do a test instead of putting a 5amp fuse in it (I will out a fuse in it later in just testing a few things now). When I got in the car and started driving it around it did good for a little bit but then as I slow down it wanted to come to a stall? It would idle at 800 rpm (keep in mind im running a Paxon 1220 supercharger. When the drops below a 1000 RPM it would fluctuate in idle then stall.I was able to make it back home and noticed that every time it falls below 1000 RPM it wants to stall so the good thing is every time I depress the clutch the car does not stall that is why I put the jumpers back on the plugs that were originally on there and unplug the clear plug just as a test to see what would happen and so far it didn't want to stall by pushing in the clutch. Keep in mind that this was an aod swap this T5 transmission is an aftermarket transmission it does not have the NSS switch inside the transmission must have came off a newer Mustang Lesson learned when buying an aftermarket transmission do your research. So moving on I idled up the idle to 1100 RPM and had no problems whatsoever I was able to drive the car continuously without it stalling it did want to drop down just below a thousand at sometimes but maintained a steady idle at 1100 where I had it set. So I'm going to do some more test I believe the culprit is in the throttle position sensor I found a good article by Jrichker that I'm going to read and test when I find the problem I will post up the results hopefully this will help someone else thanks again MustangL5L I appreciate all your help.


Sorry to revive an old thread, but I'm doing an AOD to T5 swap on my 87. My transmission I picked up does not have the NSS on the transmission as well. My pedals currently do not have the clutch switch on them either.

So what you are saying is I can leave the black plug with the red and blue wires jumpered like it is from the factory on my AOD. And keep the clear plug with light blue and green/yellow tucked into the harness, Or do I have to jumper that white/clear plug as well?

Car doesn't have Cruise Control so I don't have to worry about the plug by the accelerator.
 
Sorry to revive an old thread, but I'm doing an AOD to T5 swap on my 87. My transmission I picked up does not have the NSS on the transmission as well. My pedals currently do not have the clutch switch on them either.

So what you are saying is I can leave the black plug with the red and blue wires jumpered like it is from the factory on my AOD. And keep the clear plug with light blue and green/yellow tucked into the harness, Or do I have to jumper that white/clear plug as well?

Car doesn't have Cruise Control so I don't have to worry about the plug by the accelerator.


HI Sam, yes to the above statement---the only one you will plug in will be the safety kill switch when the clutch is depressed. The other two you would leave jumped ( pretty much how they were before). And that's your preference if you want the safety kill switch on. I hope this helps!