4lo Blinking

[Ogre75]

If it's anything like the NSBU switch on my old GMC, there very easy to replace yourself, just bolted to the side of the tranny with a plug. Though you have to make sure that if the swith is already in neutral, you put your transmission in neutral before you start replaceing it so they are sync'd

 

[BltByKrmn]

Just took my 2015 4runner in to the dealer after the 4lo light blinked intermittently 3 or 4 times over the last 12 months. They just called me and said no codes, no 4lo light on, nothing they can do. I have the 6 year 125K Platinum warranty so the repair would be covered. They told me if it was the neutral safety switch it would throw a code.
Can anyone please provide more details as to how they got their Toyota dealer to fix the problem correctly? I do go to the car wash, I do live in the northeast with wet weather.
Again, they told me it could not be the neutral safety switch because that would throw code/check engine light.
Thank you

That is 100% not true, they don't know what they are talking about. When it happened on mine it never had a CEL or code. 2 years since the neutral safety switch was replaced and the issue hasn't returned.

 

[Bossman]

I recently ran into this very same issue on my 2011 Limited with 169,000 km.

Three dash warning lights activated while driving - the Check Engine light was on; the Slip Indicator was on; and the 4-LO Lowspeed 4WD Indicator was flashing.

Using my OBD II Code Reader, the Error Code P0705 - Transmission Range Sensor Circuit Malfunction (PRNDL Input) came up.

I can't say for certain that I truly noticed that moving the gear shifter was becoming all that difficult over time.

Based on my research, I anticipated that the A/T Gear Position Sensor aka the Neutral Safety Switch (NSS) Assembly had failed.

Toyota Canada Part number for the NSS is 84540-35060.

My independent mechanic confirmed the switch failure, and after waiting several days for the local Toyota dealership to get this part in, the old switch was removed (not easily removed due to the corrosion) and the new switch was installed.

My mechanic showed me the inside of the old switch, and the internal corrosion that was on the internal contacts.

The new switch cost $263.00 CAN.

With the new switch, moving the gear shifter does seem a bit smoother

 

[Humble Leader]

had this happen today. I hadn't driven the truck for 2 weeks except two small trips (less than 2km total). 4lo started blinking when driving, no other lights. put it into 4Hi and after about 20 seconds it went away. did not return. 4Lo engaged immediately with no issues. Neutral safety switch is original on my 2012 limited (full time 4wd) with 150k+ miles. probably replace anyway? no codes so I can't scan anything or was this a fluke from not using the truck very much

and of course I need to be on the road on friday. I don't want to get stuck way out of town and not be able to shift into gear

update: CEL came on. NSS being replace by dealer but the part number has changed. will update for the current part number
update: 84540-35061 is the part number they used today

 

[bltkmt]

It is happening now on my 2010 Limited. At first it was CEL and 4LO. I disconnected the battery cables, cleaned some corrosion, touched the cables to reset things and reconnected battery. Now only 4LO is flashing. Will take it to my local guy and suggest Neutral Safety Switch.

 

[FartKnocker5000]

2017 SR5 90k miles, 4-lo light randomly stays lit

On my 2017 SR5 w/~90k the 4-lo light will randomly just come on (not blink), sometimes after starting it and other times when on the highway. No check engine light comes on though. Sometimes the 4-lo light will stay on for up to 20 minutes, then just as mysteriously, go off again.

Took it to my trusted mechanic and he said there were no codes at all. Not sure what to do, just randomly start replacing parts, like the neutral sensor switch, and work my way up to the transfer case (maybe it's a bad actuator). I called a reputable dealer and spoke to the service adviser there, he said he hadn't really heard of that happening before.

 

[Humble Leader]

On my 2017 SR5 w/~90k the 4-lo light will randomly just come on (not blink), sometimes after starting it and other times when on the highway. No check engine light comes on though. Sometimes the 4-lo light will stay on for up to 20 minutes, then just as mysteriously, go off again.

Took it to my trusted mechanic and he said there were no codes at all. Not sure what to do, just randomly start replacing parts, like the neutral sensor switch, and work my way up to the transfer case (maybe it's a bad actuator). I called a reputable dealer and spoke to the service adviser there, he said he hadn't really heard of that happening before.

some 4th gens have had that same thing happened. solution in this thread. I believe transfer case replacement. maybe start with some of the troubleshooting these guys did and work your way from there

4LO Indicator on. Not in 4WD!!

 

[indesqui]

where is the switch located?

my 4runner when trying to activate the center lock or 4LO the lights on the synoptic keep flashing

 

[BlueHenT4R]

where is the switch located?

my 4runner when trying to activate the center lock or 4LO the lights on the synoptic keep flashing

Couple of YT videos that show location and replacement:

https://www.youtube.com/watch?v=R9FUgjwq1_o

https://www.youtube.com/watch?v=dnHbbzus21A