My shifter has been getting stiffer lately and now when I shift from park to drive the D in my dash display is blank. It goes into gear fine and all the other letters, R, N, P and 1, 2, 3,and 4 show on the dash but not the D.
Last night while driving home with no D in the display I saw the Track Off come on and the Check Engine appeared.
Can anyone here guide me on what might be the issue and how to repair or inspect it? My dealer is a long way away but I am quite handy at doing most of my own repairs and maintenance.

NSS. Nuetral safety switch.

Also known as the range selector. I forget what the exact term that toyota uses is right now. It's a little box on the passenger side of your transmission. They get all kinds of bound up and cause exactly that situation. Because of corrosion.

If you search, there are a couple of long threads here with part numbers and our experiences replacing them. It ends up taking a lot more time than it should because they are usually seized to the shaft that comes out of the trans.

Mine was like a 6 hour job because it just wouldn't come loose easily. And I had to break it into several pieces to get it off.

It's on the outside of the trans, by the passenger frame rail. You get at it from underneath. Unplug the connector, unbolt very easily, taking the locking collar off first. Then have fun prying the damn thing off of there lol. Space is tight but anyone can do it, eventually.

Sent from my SM-S901U using Tapatalk

I had mine replaced in 2022, had to original from 2012 on there. PN was
84540-35061

Yep, classic neutral safety switch. 5 minute job... unless you have rust problems, which is the cause of the switch going bad to begin with.

Thanks Ken, very informative!

Could the switch also be referred to as the "Indicator Switch"?

The reason I ask is because I have the Toyota Platinum service contract that is still in effect. It specifically lists the indicator switch as a covered item.

Indicator switch in Asia and Europe is the turn signal switch but the dealer should know.

Thanks Sparticus, I should have said "Gear Indicator Switch". Seems everyone has a different term for what it is really listed as but I have not seen the actual Toyota part name.

Since you have a 2016 model. It's Toyota 84540-60050 Switch Assy, Neutral Start. I got that part number after putting the Vin for my 2016 in the parts catalog.

edit: It is also referred to as, gear position sensor.

They changed the part number in 2017 to the one you have referred. for 2007 to 2016 the part number comes up as Toyota 84540-60050Switch Assy, Neutral Start. Not quiet sure if they are interchangeable.

Sounds like the NSS must be a common issue. I had the same symptom a couple years ago on my 2015. In my case there was corrosion in the shift linkage where the cable terminates at the transmission. If I remember correctly it’s a bal and socket. I cleaned as much rust off as I could and sprayed the l8nkage with penetrating oil while I had someone work the shifter back and forth. Once it was working normally again I coated it with grease and it hasn’t caused an issue since. Might be easier and cheaper to try first.

Good luck!

My 4R is at the dealer now. Codes read Neutral Selector switch. All covered under my extended platinum warranty but they don't have the part in stock so I will be driving their loaner for the next 4-5 days or until they can get the part.

Now to add to the Saga. So my 4R is now 7 years old with 49K on it. Dealers have to generate profits. They advised me that I need to have the transfer case, front and rear differentials and the transmission fluids changed. Only about a $900 service. I said NOPE! Not sure what you all think but I think this is absolutely ridiculous. I do all my own normal maintenance like oil and filters and brakes and pretty sure I can also do the differential fluids but the tranny is another one I probably can't DIY. Any opinions from those who really know?

Diffs are pretty straight forward. Open the fill plug before undoing the drain plug. Get some new gaskets, diff lube of correct weight. Atf is a a little more challenging procedure but still diy. I will probably have the dealer do it on my atf service but will have to pay more for them to use Toyota ws at fluid instead of the bulk stuff they use.
Beginner Fluid Maintenance

NSS replacement was covered by Platinum Plan for me.

Seems like this cleaning and lubing procedure should be added to the PM schedule. At least for the DIYers. What grease did you use? Your instructions imply you didn’t actually remove it from the transmission?

I hope to get the faulty NSS after the dealer replaces it with a new one. I want to tinker with it to try and determine exactly what caused the failure or where/how the moisture got in it to cause the issue. I doubt this switch can be taken apart and put back together after a deep cleaning but it is just my nature to see what makes the clock tick.