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Discussion Starter #1 (Edited)
Neutral safety switch Auto tranny bypass

New to me 1999 TJ Sahara. real nice rig. First jeep. Lovin it!
Engine light on when bought. Prev owner said it was due to a bad NSS. He was right. I replaced NSS. I checked operation of NSS to be sure:
Continuity between center pin and tran case when in Park or Neutral only. Continuity between outer pins on NSS when in reverse. Engine light off. Jeep starts fine. Reverse lights work. However, engine will still attempt to start when in any gear. I wish to set this back to factory for safety reasons. Circuit must have been bypassed by previous owner. Can anyone tell me if there is a factory setting on this before I start tracing wiring harness?

Also, prior to work done engine would start in any gear which is why I assume prev owner bypassed NSS.

Thanks, Ray
 

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New to me 1999 TJ Sahara. real nice rig. First jeep. Lovin it! Engine light on when bought. Prev owner said it was due to a bad NSS. He was right. I replaced NSS. I checked operation of NSS to be sure: Continuity between center pin and tran case when in Park or Neutral only. Continuity between outer pins on NSS when in reverse. Engine light off. Jeep starts fine. Reverse lights work. However, engine will still attempt to start when in any gear. I wish to set this back to factory for safety reasons. Circuit must have been bypassed by previous owner. Can anyone tell me if there is a factory setting on this before I start tracing wiring harness? Also, prior to work done engine would start in any gear which is why I assume prev owner bypassed NSS. Thanks, Ray
If it started at all with a bad NSS it had to be bypassed. There is typically a manual override in the center console in case it goes bad away from home. I would "assume" he bypassed it there, that's what I would do.. Typically there is a small square pop out cover next to the gear selector cover on the driverside.

Edit.. Just remembered, my 99 had a fuse that I could pull allowing my jeep to start without clutch compressed, might be a fuse for the NSS bypass. Not sure about that
 

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Discussion Starter #3
If it started at all with a bad NSS it had to be bypassed. There is typically a manual override in the center console in case it goes bad away from home. I would "assume" he bypassed it there, that's what I would do.. Typically there is a small square pop out cover next to the gear selector cover on the driverside.

Edit.. Just remembered, my 99 had a fuse that I could pull allowing my jeep to start without clutch compressed, might be a fuse for the NSS bypass. Not sure about that
Thanks I will check it out. By the way, mine is an automatic tranny. Make any difference?
 

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Thanks I will check it out. By the way, mine is an automatic tranny. Make any difference?
My edit was for a clutch safety switch, you won't have that, but there might be one for a NSS.. Not sure.
 

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Discussion Starter #5
just walked out and checked it. I see no cover in or around gear shift/center console. I will keep digging. Thanks again!
 

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Ugh, that's because I'm an idiot anyway. It's a Manual Brake lock override. So you can shift out of park if the lock fails.

Here's a picture, not all are this clearly visible, or marked.. But not what your looking for anyway.



image-3669476641.jpg
 

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Discussion Starter #8
Prob solved! Jumper at C154 needed to be removed. Access thru floor under shifter console. It is used when manual trans is used as apposed to automatic. No need for NSS with manual trans. When NSS malfunctioned, owner obviously knew this or took it to a shop who knew this and installed tiny jumper inside this connector. Did not want to spend $22 for new NSS.
New NSS is working properly and no check engine light.
 

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Prob solved! Jumper at C154 needed to be removed. Access thru floor under shifter console. It is used when manual trans is used as apposed to automatic. No need for NSS with manual trans. When NSS malfunctioned, owner obviously knew this or took it to a shop who knew this and installed tiny jumper inside this connector. Did not want to spend $22 for new NSS. New NSS is working properly and no check engine light.
Nice!! Gotta love it when people are too cheap to pick up a $20 part to fix things right..
 

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Discussion Starter #10
I hear ya!
Next step: new rear main seal and oil pan gasket. Slight oil leaking on my new driveway.
Looks to be pretty straightforward. I think getting the exhaust bolts off would probably be the biggest hassle.
 

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I hear ya! Next step: new rear main seal and oil pan gasket. Slight oil leaking on my new driveway. Looks to be pretty straightforward. I think getting the exhaust bolts off would probably be the biggest hassle.
Spray, spray, spray, spray. Lots of penetrating oil..
 

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Thanks I will check it out. By the way, mine is an automatic tranny. Make any difference?
New to this site. I have a 2002 Sahara. Also automatic transmission. The bypass fuse in mine is number 20. It is behind the glove box. The info tag on the glove box as notes this.
 
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