Neutral Safety Switch On Pass Side??

jraap82

Active User
Aug 29, 2016
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5
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So after we (my 11 year old son and some awesome stangnet members!) figured out why I couldn't get my car to even crank, now it fires right up and still has an idle surge problem. I am pulling a code 67 as well and want to get that fixed first before I start rolling through the surging idle checklist. I know for a fact that the neutral safety switch isn't plugged in because the harness under the car is just hanging there and there's no harness coming off the transmission. Everything I've seen online says the switch is on the drivers side, top of the trans cover. The question I have is, is it at all possible that the switch is on the passenger side? If so, where can I find the correct sensor with a long enough pig tail? I've only seen one post on a random forum where a member said his was on the pass side on his T5 and another guy said they only did this on the 1985 T5's. My car is an 89 GT and the trans code on the door sticker is 2. I've only had the car for about a year so I'm not sure if the trans is even the original one. We've already reinstalled the transmission after the engine rebuild so I can't get the greatest look at it, but looking at pics from when we pulled it, it looks pretty obvious that the sensor is still in the hole on the passenger side and the harness was cut off it. Any info is much appreciated!

-Joe
 
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Passenger side NSS is a sign of a non-World Class T-5, which was installed in the 1983-1985 Mustang.

1985.5 went world class, and at that point the sensor changed over to the driver's side. The sensor is NOT interchangeable with the driver's side NSS version. The threaded portion is a different diameter, and the connector is different. You'd really need to cut and splice the later connector, with the earlier sensor and create a sort of hybrid harness.


Here's a 1985 T5 I had that shows the switch on the passenger side. This is a non-WC t-5.
pic.php?u=11130S5RAi&i=542001.jpg





OR...locate the two plugs under the dash connected to the clutch pedal. One is the starter circuit, and the other is also part of the NSS circuit wired in parallel with the switch on the trans. Unplug the NSS plug (you'll know you have it if you can still start the car by pushing clutch in) and jump it with a 5A blade fuse.

That should take care of code 67. If it doesn't...the wiring harness may be mixed up as well
 
Last edited:
Passenger side NSS is a sign of a non-World Class T-5, which was installed in the 1983-1985 Mustang.

1985.5 went world class, and at that point the sensor changed over to the driver's side.


Here's a 1985 T5 I had that shows the switch on the passenger side. This is a non-WC t-5.
pic.php?u=11130S5RAi&i=542001.jpg





OR...locate the two plugs under the dash connected to the clutch pedal. One is the starter circuit, and the other is also part of the NSS circuit wired in parallel with the switch on the trans. Unplug the NSS plug (you'll know you have it if you can still start the car by pushing clutch in) and jump it with a 5A blade fuse.

That should take care of code 67. If it doesn't...the wiring harness may be mixed up as well
The sensor is NOT interchangeable with the driver's side NSS version. The threaded portion is a different diameter, and the connector is different. You'd really need to cut and splice the later connector, with the earlier sensor and create a sort of hybrid harness.

Thanks for the quick response and great info!! I would've never even thought to verify if the harness plug was different between the two, so that definitely saved me some headache and cash. I'm going to verify all the wiring is still in tact to the switch by the pedal to be safe because someone did a hack job with trying to bypass everything else on the car already. Once its all normal minus the nss being hooked up, I'll try the 5A blade fuse until we get to the point of replacing the transmission down the road. Again, greatly appreciate the info!

-Joe
 
Wiring looked good so slapped a fuse in it and it was definitely the majority of the problem with the idle surge. Still idling kind of rough but its not surging up then hunting and stalling out anymore. I still have code 67, but one of the PO's bypassed the clutch safety so it may have something to do with that? I'm going to go ahead and do a base idle reset, along with checking everything on the checklist and see if that helps it get to where it needs to be. Thanks again for the info!
 
Code 67 has nothing to do with the clutch safety. Make sure you really have the code 67 first by erasing all the codes, and then rerunning them. Either pressing the clutch in (or using the jumper) or having the t-5 in neutral will eliminate the code 67

If you still have the code 67 with that jumper in, it's possible there's a mismatch of wiring harness/ECU's. You might want to start a new thread for that. Possible you have an AOD computer in the car, with the o2 harness pinned for a 5-spd, or nice versa
 
Code 67 has nothing to do with the clutch safety. Make sure you really have the code 67 first by erasing all the codes, and then rerunning them. Either pressing the clutch in (or using the jumper) or having the t-5 in neutral will eliminate the code 67

If you still have the code 67 with that jumper in, it's possible there's a mismatch of wiring harness/ECU's. You might want to start a new thread for that. Possible you have an AOD computer in the car, with the o2 harness pinned for a 5-spd, or nice versa

Ok, thank you for the heads up. I'll make sure to clear the codes first and then see if it pops up again now that the fuse is in there. If so, I'll definitely start looking into the other possibilities that you mentioned.

-Joe
 
Cleared the codes then ran the KOEO and got an 11 which is good. Then ran the KOER test and got a 66 and 98. I found a checklist on here to troubleshoot 66, but I'll post a new thread for some help on that. Thanks again!

-Joe
 
Passenger side NSS is a sign of a non-World Class T-5, which was installed in the 1983-1985 Mustang.

1985.5 went world class, and at that point the sensor changed over to the driver's side. The sensor is NOT interchangeable with the driver's side NSS version. The threaded portion is a different diameter, and the connector is different. You'd really need to cut and splice the later connector, with the earlier sensor and create a sort of hybrid harness.


Here's a 1985 T5 I had that shows the switch on the passenger side. This is a non-WC t-5.
pic.php?u=11130S5RAi&i=542001.jpg





OR...locate the two plugs under the dash connected to the clutch pedal. One is the starter circuit, and the other is also part of the NSS circuit wired in parallel with the switch on the trans. Unplug the NSS plug (you'll know you have it if you can still start the car by pushing clutch in) and jump it with a 5A blade fuse.

That should take care of code 67. If it doesn't...the wiring harness may be mixed up as well
Had a question on this as I also have an 85 T5 but mine seems to be world class and DOES have the top switch on passenger side. On the ASTRO T-5 id / interchange page it mentions that 85 switch was an "overdrive indicator switch" on top? Also my id tag say 13-52-126 which decodes to 1985 t5 WC.

Quote from page
"Is there a neutral switch on the top cover?
The 86-93 V-8 Mustangs all need the neutral switch.
The 1985 V-8 Mustangs had an "Overdrive Indicator" switch on the passenger side of the top cover. "

What would this wire into, an overdrive lamp on the instrument cluster? Curious as I am swapping this 85 T5 into my 86 AOD hatch.

Thanks!
 
The 85 1/2 up T-5 is the same up until 1993. The purpose of the connector changed. In 1986, it was required for fuel injection to know when the trans was in neutral so it could modify it's idle strategy slightly. It was also used for the purpose of pulling codes.

What you may need to do is remove the sensor on the top case of the T5 and swap it to an 86-later NGS sensor to be compatible with your 86. The wiring harness plugs changed dramatically between 1985 and 1986, so my thought is that the 1985 sensor won't plug into your 1986 wiring.

Does the plug end look like this?
 
No, it has a much larger connector with 2 blades not pins. Will a later switch work in this position?

It should. Have a pic of the top cover and the borg-warner part number stamped into it? It should be something like 1352-080-xxxx. I have a late model top cover sitting on a bench. I can grab the number tonight and confirm
 
here is a cut and past from Astro t5 ID page for 13-51-097-901 and you can see the plug has 2 blades and the large connector, My 86 AOD harness has same connector but 4 blades. FYI - I have both t5 trans harness (with smaller pin connector) and t5 02 harness on hand as well as the stock Auto harnesses.

Top Cover CASTING NUMBERS:
13-52-097-901 Early style plain top - Ford & GM (no neutral switch)
13-51-097-901 85 Ford w/neutral switch on RIGHT SIDE
 
The AOD neutral switch is completely different. This is the one that won't let the car start unless the trans is in neutral. It's 4 pin, and 2 pins are the reverse lights. When you swap to a T5, the small plug has a jumper in it. This jumper is for the AOD neutral start switch.


You can see the red jumper in the harness. This jumps out the NSS for the AOD.


The plug on top of the T5 is actually called the NGS. It plugs into a different plug that isn't present on the AOD transmission harness. The trans harness runs from the driver's kick panel, out the trans hump and to the transmission. On the AOD it only has two plugs. One for the VSS and one for the neutral start/reverse lights that plugs directly to the AOD. On the T5 harness, there is a 3rd plug...the NGS plug that connects to the top plug on the T5.

So if you are doing a 5-spd swap on an AOD car, you need to change out this entire harness to get the proper plug. OR, you can cut the connector off, solder or crimp on 2 longer wires, and run them over to the driver's kick panel and tap into the proper wiring in the panel. Same thing.

Also, 1986 O2 harness does not have the jumper for the starter circuit running through it. It's wired differently and doesn't go through the 2 harness. No need to change anything here. The repining of the O2 harness starts for mid-1988 and up cars.
 
ok, just for further info if it makes a difference my 86 is Mass Air converted with a C3W ecm (Mass Air, Auto ecm)

my stock AOD harness is much shorter and is connected behind the stereo, is there another plug in the kick panel for a manual? the manual harness is much longer so that would make sense if the newer cars had the plug in the kick panel area.

also it is ok to run my 86 AOD O2 harness without damage to C3W ecm?
 
You'll want to test pin 46 on the ECU. This is what typically causes ECU's to fry when they have voltage on this pin when they shouldn't.

See this post for testing procedures

 
You'll want to test pin 46 on the ECU. This is what typically causes ECU's to fry when they have voltage on this pin when they shouldn't.

See this post for testing procedures


Will do
 
what about the harness? ok to plug the longer manual harness into the original plug that was behind the stereo, it is a match both 8 pin etc.

Unsure. I don't have the EVTM wiring diagrams for an '86 so I don't know if that is the plug or not. I'm more knowedgeble in 1987+ cars. Only played around with a handful of '86's.