Neutral Safety Switch

**ctys20** · 11-04-2009, 01:10 AM

Hi everone,

I just put a new transmission in my year 2000 Silverado. The only problem I've had so far is that the gear selector does not work correctly - reverse doesn't appear but the transmission does go into reverse, Neutral doesn't appear,and Drive is Neutral.

When operating the gear selector I can hear the transmission go through P-R-N-D but as stated the indicator is not working.

I was unable to get my old neutral switch off the old transmission (it felt like it was glued on). I had the transmission rebuilder install a neutral switch on the new transmission - and I suspect that is the culprit.

Any ideas?

If it is the switch is there a trick to taking them off? And when installing what gear should the transmission be in?

Thanks,

**ctys20** · 11-04-2009, 08:02 PM

Update: Apparently, if you loosen the bolts holding the switch onto the transmission the entire assembly will swivel. Since the computer thought the transmission was in neutral when in drive I rotated the switch counter clockwise and it now appears to work.

This does seem a bit tacky but the bolt holes are drilled to allow adjustments.

Also, when removing the plugs I had to use a torch to lightly heat them as they are glued from the factory - cleaning the contact points is also a good idea after removal.

**unplugged** · 11-04-2009, 08:21 PM

Great info. Would be over the top with pics for the noobies. Thanks for helping GMTC be the best place to go for Truck info!

**Mumbles** · 02-17-2010, 10:04 PM

My dad has a 97 S10 4x4 Pickup with the 4.3L and the 4L60E Automatic Transmission.

Two years ago his transmission began to slip and we replaced it with a used tranny from a 96 Blazer. Truck was good to go again.

Over the past year it has developed a problem with the ignition on the steering column not wanting to rotate back far enough to release the key when the vehicle is shut off. He found, if he jiggled the floor mounted shifter, the ignition would rotate to the correct position and he would be able to remove the key. This little quirk tells me that the problem must have something to do with the Neutral Safety Switch believing the vehicle is not in Park. Correct?

Well the "jiggling" is nolonger working and the key it stuck in the ignition.

I've consulted my Chiltons and Haynes Manuals and they both tell me there is a Neutral Safety Swith Adjustment tool that can be rented from a parts store that can be used to adjust the switch that is located on the transmission.

I've called all the local parts stores and none them have any idea what I'm talking about when it comes to this Adjustment Tool.

I spoke with a local mechanic about the problem. He told me to check beneath the consel to be sure the wiring hasn't come unplugged from the switch on the shifter.

I currently have the consel apart and everything seems to be connected properly.

Here are my questions...

First of all, which switch should I attempt to adjust and/or replace? The one on the tranny or the one on the shifter?

Secondly, if the switch on the tranny is the one to replace, how do I properly adjust it, with or without this mysterious adjustment tool?

Thanks to all who reply. If there are any other details you may need in order to properly diagnose this problem, please ask and I will try to provide them in a timely manner.

**Mumbles** · 02-17-2010, 10:24 PM

I thought I should add, the pickup starts and drives just fine. (Well, as well as any vehicle with 260,000 miles. LOL)

Anyways, if you have any ideas, I'm all ears.

**Jimmiee** · 02-18-2010, 08:21 AM

Originally Posted by Mumbles

I thought I should add, the pickup starts and drives just fine. (Well, as well as any vehicle with 260,000 miles. LOL)

Anyways, if you have any ideas, I'm all ears.

If your problem is just getting the key to come out it has nothing to do with the neutral safety switch. You need to adjust the linkage rod or cable that goes from the trans to the column.

**Mumbles** · 02-19-2010, 03:49 AM

Originally Posted by Jimmiee

If your problem is just getting the key to come out it has nothing to do with the neutral safety switch. You need to adjust the linkage rod or cable that goes from the trans to the column.

Thanks for the reply. I inspected the linkage prior to posting and everything seemed to be fine. I'll take a second look the first chance I get, though.

I suppose if it were the NSS and it believed the vehicle was in gear, it wouldn't allow the truck to start. So your advice makes sense. Thanks Jimmiee.

**Mumbles** · 02-22-2010, 06:32 PM

Originally Posted by Jimmiee

If your problem is just getting the key to come out it has nothing to do with the neutral safety switch. You need to adjust the linkage rod or cable that goes from the trans to the column.

Would this be true for the factory floor mounted shifter, as well?

As far as I can tell the only connection between this shifter and the steering column is electrical. (As opposed to mechanical via the linkage.)

Mmm... maybe this would be a good topic for a new thread. Thanks...

**Jimmiee** · 02-23-2010, 03:34 PM

Originally Posted by Mumbles

Would this be true for the factory floor mounted shifter, as well?

As far as I can tell the only connection between this shifter and the steering column is electrical. (As opposed to mechanical via the linkage.)

Mmm... maybe this would be a good topic for a new thread. Thanks...

I'm not too familiar with the operation of the floor shifter and how it's linked to the ignition switch lock out.

**montana-bob** · 06-23-2010, 08:41 AM

Does someone know definitively if the plugs that go into the neutral-safety switch are glued or not? I have a friend who worked for GM PowerTrain who still rebuilds transmissions on the side and says they are. I have a dealership telling me that GM has put a bulletin out indicating that the reason the plugs are hard to get out is because of high heat.