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Discussion Starter #1
The Neutral Safety Switch or Gear Position Sensor costs about $277 at the time of this article and before dropping the bucks I decided to see if the switch could be repaired.

I got the idea from a brief description written up on another site and decided to try the technique BEFORE dropping $277 and IT WORKS!!!

Before you jump off and do this, please read the instructions here all the way through, it will save you tons of time! Speaking of which, its about 30 minutes to get the NSS out and another 30 to put it back in. It took me another two hours to drill out the rivets, clean everything, a trip to the hardware store to get replacement screws etc. Total time: 3 hours! Total Cost: less than $10!!!

You will need the following:
9 each 6/32 x 3/4" machine screws with nuts.
a small amount of dialectric lube
a small amount of high temp lube (wheel bearing grease worked for me)
a philips head screwdriver
a pair of pliars
a wire brush
a can of electrical contact cleaner
a drill & bits
a pair of goggles (wear them while drilling)
PLUS the tools listed at the link in the next paragraph

First, we'll begin by removing the NSS. Instead of going through the explanation of how to do that, there is a really great set of instructions with awesome pictures here:
http://www.scribd.com/doc/100542/DIY-Saab-95-Neutral-Position-Switch

After you get the NSS out it should look like this:


Next you want to drill out the rivets as marked in this next photo. Technically, all you have to do is shave off the waffle head and the rest of the rivet will come out the bottom. The rivets are solid aluminum. Becareful not to open the case just yet, there are parts inside you could loose!


Once you get ALL the rivets drilled out, flip the unit over so that the top (metal side) is facing down and gently pry the unit apart. Be careful as there are six loaded springs inside about the size of what you'd find inside a clikable ball point pen and on top of these springs are tiny horseshoe shaped contacts. Once the unit is apart it should look like this:


This next picture shows the springs/contact pairs sitting in their ceramic holders (3 in each) and the ceramic holders sit in what looks like a spindle armature. This picture is blurry (best I could do) but shows a lot of dirt on the little contacts.


Here is a side view of the spring/contact pairs sitting in the ceramic holder:


Here's another view of the contacts, it's important that you know how these go back together or you will have wasted a lot of time:


Here is a side view photo of the spring and brush (contact) out and cleaned:


Here is a photo of the empty ceramic holders still in the armature. These ceramic pieces only fit in one way so you can not possibly get them confused or mixed up.
 

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Discussion Starter #2
The bottom section (black plastic part with wires) contains a gold plated set of contacts and this needs to be cleaned:

Here is the completely disassembled and cleaned unit ready to go back together. Put some grease in the tray of the top (metal) part and rub it around evenly. I also applied what was left on my finger to the bottom of the armature and then wiped down the sides. Next I placed the armature back in the top, inserted the ceramic holders and then VERY carefully inserted the spring/contact pairs (yes, I did drop at least 1 pair in the grease and had to reclean them). Then I put a very thin coating of diaelectric grease on the gold plated contacts (and I mean a VERY thin coating!) and when that was done I oiled up the gasket and reseated it. To reassemble, I put the bottom piece on top of the top piece (otherwise the springs would fall out!) and started at the heel (section outlined in the green box:


Getting the screws in was a little tricky... some of them slipped right in while some took a little coercion from the pliars but they all went in. I put the first two in on opposite corners and tightened them down so that I could work more freely without fear of the unit coming apart and me having to start all over. Make sure to insert the screwheads from the bottom side (black plastic piece):


I tightend the nuts down as tight as I could with a screwdriver and then put clear locktite on them (sorry, didnt have any other color).




I then followed the instructions for reinstalling as found in the document on scribd.com on how to remove the NSS... make sure you test your park, neutral starting ability AND that your back-up lights worked. My were dead on straight away the first time (the shifter cable kinda tells you where you should be!).

Thats it... some dirty hands and some bench time was all it took but it saved me $270!!!
 

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Cracking post definitely one for the FAQ's :p
 

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Discussion Starter #4
Glad I could help... if nothing else, everyone will know whats inside that little bugger (certainly NOT $277 worth of anything! LOL).

Essentially, there are no electronics inside this part and unless the wires have come loose from where they are attached in the bottom section, this SHOULD fix the problem.

Here's a link to the original post:
http://www.saabnet.com/tsn/bb/9-5/index.html?bID=207701
 

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Definitely and excellent write up!

This looks EXACTLY like the PNP switch in the Volvo 850 T5 I had. It also had an A-W transmission.
 

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See this is why this is the best forum, pictures really help and the fact that someone has taken some time to help others by writing all this up is awesome!
 

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Discussion Starter #9
I'm curious, the gold plated contacts or the spring loaded contacts? How many miles?

I have 175,000 on my 2001 9-5 and I couldn't see any place on either side that was worn that badly and I looked closely.

Way I figure it, all one has to loose at that stage is drilling out 8 or 9 rivets to find out... that was my approach... nothing to loose by looking and everything to gain!
 

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Yep, my Volvo had 172K on it when I cleaned up the dried up grease, dirty contacts and contact dust. The contacts were still in great condition.
 

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Then I put a very thin coating of diaelectric grease on the gold plated contacts (and I mean a VERY thin coating!) and when that was done I oiled up the gasket and reseated it. To reassemble
I assume you emphasized the thin coating of dielectric grease because too much would inhibit current from passing between the contact and gold/copper trace.

Do you think it is necessary to grease the tracings at all? Do you think it came greased originally? (not that the way it came from the factory was necessarily good...)


Awesome DIY. I am attempting this now. I have the NSS out and am about to start drilling it.
 

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Discussion Starter #15
I followed the directions posted by another user on another site (link to that post is up there somewhere).

A very thin coat if dialectric should not matter and, once you get it apart and put it back together (dry run) and turn it you'll hear why it probably needs some lubricant.

I hope it works... if there are any differences or it doesnt work, be sure and post back!
 

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Great post. Thank you!. In one of the other posts about this procedure, the poster used dielectric grease on the contacts, then after a few weeks re-opened the unit and found the grease had turned green and seemed to be preventing proper function. He then used petroleum jelly instead. Any follow up issues with the dielectric grease?

Chris
 

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Discussion Starter #17
Not in my case but the old girl doesnt get driven as much as she used too... maybe 10-20 miles a week.

I googled "dialectric grease + grease" and found no references where it turned green or made connections turned green... in fact, just the opposite.
 

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To add to this excellent post ! I got some good advice from an Indie Mechanic...my Neutral Switch starting acting up when the car was warmed up it would not start because of the fault...He told me to wait until the engine is warm...so drive around for 30 minutes or so...and take electrical cleaner and spray it all over the top of the switch getting all the connectors etc..he said this will cause the grease to losen up and clean the connectors...I did this and the switch has worked flawlessly for 6 months now/
 
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