2016 Leaf steering stiction

[jame...@whidbey.com]

Requesting advice on '16 Leaf steering problem.

Steering wheel stiction has been increasing. I have noticed it for a year; my wife only for couple weeks, and she see it as the car wandering, which it isn't. If one stops steering wheel rotation in exactly the right position, the car will go straight ahead. But that doesn't often happen. The new position usually is not perfect, it's slightly off, so the car heads that way. Subsequent wheel corrections from a stationary wheel position can have the same problem, so it's easy to 'wander down the road' trying but failing to move the wheel small amounts.

It's not terrible, but it is a pain that mounts with drive time.

The symptom I experience is 'stiction' in the initial effort to turn the wheel. Once rotation has begun it is easy to continue. I know little about EPS electric power steering, but can't think of any mechanical reason for stiction because there are so few mechanical connections, and because one the wheel is in motion it is easy to alter wheel angle.

I find very little on this topic for electric power steering, in fact just one site which does not manage to relate real life instances:

snip:

Electric power steering failure symptoms

Electric power steering (EPS) is a vehicle steering system that uses an electric motor to assist the driver in turning the wheels. This system replaces the traditional hydraulic power steering system, which uses hydraulic fluid to help the driver. EPS is a newer technology that offers several advantages over hydraulic power steering, including improved fuel efficiency and reduced emissions.

Plus, it is more reliable as there are fewer chances of failure due to a lesser number of working components. For example, there is no power steering pump or fluid leaks, and you don’t need to worry about the power steering fluid levels because there is none. EPS is not without its disadvantages, it can be more expensive to repair yada yada.........

The two of the most important sensors in the EPS system.

1. Torque Sensor:

The torque sensor determines the amount of assistance provided by the electric motor. The torque sensor measures the force the driver exerts on the steering wheel and sends a signal to the electronic control unit (ECU). The ECU then determines how much assistance to provide from the electric motor.

2. Speed Sensor:

The function of the speed sensor is to measure the wheels’ rotating speed and send a signal to the ECU. The ECU uses this information and input from the torque sensor to determine how much assistance to provide from the electric motor. Some cars employ a separate steering angle sensor to measure the angle of steering as well.

Symptoms

1. EPS Warning Light

2. Loss of Power Assist

3. Vehicle Pulling to One Direction

4. Whining Noise From Power Steering Motor

5. Soft Steering Wheel at High Speed

6. Vibrations From Steering Rack

 

More at:

https://completecar.ca/maintenance/electric-power-steering-failure-symptoms/

 

I have none of the 6 symptoms just above.

The only similar account I've found is one person (not Leaf) whose power steering strength decreased, and corrosion in an electric connector was found.

I know I can take it to a dealer and they will be happy to throw parts at it, but I'm looking for a SEVA thinker who might be able to give whys and wherefores as to possble causes

BTW the 'moan from 45-58mph' I asked SEVA about is still there, unchanged. I just haven't wanted to deal with the hassle, and its only a short range car now. If it had freeway use I'd be pulling my hair out. My next two steps will be to take it to the tire place that put on the new tires and have them 'put on the rack', which I have about zero faith will yield any cause so I'll get something they make up. And the second step is to take it to a tire place I trust and ask them to drive it 45-57 for enough distance  for them to get tired of the noise and get their opinion. It's at 109k miles which to me is a brand new car so I don't imagine any bushing or steering ball joint failures, and besides, the onset of the moan was instant.

Thank you.

--J

 

 

[Paul G.]

Is it possible that the sensation of stiction is actually a decrease in sensitivity by the steering torque sensor? It could cause a sensation that feels like breaking static friction and result in over-correction in fine steering adjustments. 

Paul G.

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[Tracy Farwell]

Given the choice I would always opt for mechanical steering.  That option is often not available.  If it's EPS, it involves software.  The fundamental characteristic of software is that before, during, or after you buy it with your car, you do not and will never know how it works.

There is something that existed prior to software:  linear analog control theory.  The last thing you want in your steering control is hysteresis.  Basically a dead spot in your range of control.  Seems like that is a description of your concern.  I would put it on the rack, the kind of rack where you can have someone operate the steering and look for a loose mechanical connection, like an-egged out bushing.  A grease pit would be best because friction from tire to floor could be a factor.  

Unless you can associate the undesirable behavior with a software update or a new steering module, it will not involve software.  The best thing about software is that it doesn’t wear itself out or change itself.  One exception:  have you parked it next to a substation 1000 kVA transformer?

I would persevere with conclusive trouble shooting.  You could find a safety flaw for a multi-OEM EPS recall.  Regards, TF

I know I can take it to a dealer and they will be happy to throw parts at it, but I'm looking for a SEVA thinker who might be able to give whys and wherefores as to possible causes

BTW the 'moan from 45-58mph' I asked SEVA about is still there, unchanged. I just haven't wanted to deal with the hassle, and it's only a short range car now. If it had freeway use I'd be pulling my hair out. My next two steps will be to take it to the tire place that put on the new tires and have them 'put on the rack', which I have about zero faith will yield any cause so I'll get something they make up. And the second step is to take it to a tire place I trust and ask them to drive it 45-57 for enough distance  for them to get tired of the noise and get their opinion. It's at 109k miles which to me is a brand new car so I don't imagine any bushing or steering ball joint failures, and besides, the onset of the moan was instant.

Thank you.

--J

 

 

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[David Alspaugh]

Some thoughts James:

1) Perhaps the column mounts are loose? Thinking being that if you are moving the wheel, but the column is shifting instead, the torque sensor may not pick up on the fact that you’re attempting to move the wheel since the whole relative assembly is shifting therefore delaying it applying torque assistance. 

2) the torque sensor itself is simply losing calibration or it’s dropping signal and reverting back to some desensitized operating state to make sure some assistance is provided but it may not be optimal. Safety related systems like steering should have these redundancies. It’s possible Nissan can recalibrate this but it’s also possible they will just replace things. 

There should be an EPS sub module that is logging an error that is not necessarily user displayed. Not sure on Nissan’s particular system. 

It’s particularly strange that straight isn’t always straight because it appears on a quick look that there is still a mechanical link between the steering wheel and the wheels. Loose mechanical linkage downstream like tie rods and tie rod ends could play havoc with the calibration of the system too. Do you notice any “slop” when you’re switching from a hard left back to the right or vice versa? Has the car’s alignment been checked? Any clunks going into potholes? 

HTH,

Dave 

Sent from my iPhone

On Jan 11, 2026, at 17:08, 'Paul G.' via SEVA Email List <SEVA...@googlegroups.com> wrote:

Is it possible that the sensation of stiction is actually a decrease in sensitivity by the steering torque sensor? It could cause a sensation that feels like breaking static friction and result in over-correction in fine steering adjustments. 

To view this discussion visit https://groups.google.com/d/msgid/SEVA_list/8CEC7B8D-A134-4800-B89C-B4CE9A547168%40comcast.net.

[Eric Eskilson]

James,

Searching online a few years ago, I managed to find a nissan-leaf-2013-factory-service-manual.pdf that is 5,122 pages long. As you would expect, this manual has tons of detail. 

My 2013 Leaf has the standard rack and pinion steering layout with a torque sensor in the steering column, near the EPS (steering assist) motor. The EPS motor drives a ring gear on the steering wheel shaft, about a foot forward of the steering wheel. The EPS motor is controlled by the EPS control unit (mounted on the steering column) which communicates with the VCM, ABS and Combination Meter (dash display) via CAN. On this system, all of the "control magic" happens inches from the torque sensor, under the dash. 

The manual has varous checks for backlash and torque at the steering wheel in addition to electrical and communication checks. However, if there is a problem, they want you to replace the entire steering column assembly. 

Lacking any better information, I'd be tempted to disconnect/reconnect all of the connectors (about 6) at or near the steering column and see if that helps.

If you can find a manual for your 2016, great. If you can't, let me know outside of the group and I'll send it to you directly.

Eric

[Matt Simerson]

> On Jan 12, 2026, at 12:49 PM, Eric Eskilson <eskilsone...@gmail.com> wrote:
>
> <snip>

> Lacking any better information, I'd be tempted to disconnect/reconnect all of the connectors (about 6) at or near the steering column and see if that helps.

This is good advice when chasing a potential electrical gremlin, especially on older vehicles. While you have those connectors apart, spraying them with contact cleaner (or brushing and coating with a dab of dielectric grease), is often restorative and is also good preventative maintenance.

Also pay attention to the condition of the wire insulation in that area.

Matt

[jame...@whidbey.com]

Matt, Dave, Tracy and Paul for your replies. Some answers RE your
suggestions:

RE decrease in sensitivity of steering torque sensor STS, or steering
torque sensor losing calibration: Apparently a moot point: Nissan and
others do not list a power steering torque sensor for the '16 Leaf, only
a steering wheel position sensor SWPI which is supposed to act with
traction control. I don't find enough info on the position sensor to see
where it could affect felt resistance of the wheel only at the attempted
initiation of wheel movement. There are two
SWPI's listed at one location: PN 47945X or 25554. Lookup of PN 47945X
says that it fits 05 to 2013 Leaf at $177, and not '16 SV. Elsewhere
says the part that does fit is 47945-3FYOA at $778.39, MSRP $1099.42
ouch.

RE contact cleaner and dielectric grease: Yes good reminder, I have
both, but getting at wiring involves some of the same steps as R&R of
the STS; the one drawing I found appears to require removal of steering
wheel, removal of PN 25554, and then R&R of 47945X and
reassembly........when 47945x perhaps isn't the right part. Meaning air
bags and a degree of familiarity with that area that urges against
beginner attempts.

RE mounts loose....I assume that includes all of them, most of them not
having seen the light of day since 2016, all in places I don't want to
go and above my Soc Security pay range.

RE mechanical steering gear slop. 109k odom means brand new to me and at
least 50k less than any other vehicles around here. More importantly,
the Leaf has always been and remains a laudably tight chassis and
suspension. No looseness I can feel either over bumps, swales or
cornering. And while I tend to drive as a hypermiler today, it doesn't
mean I'm unfamiliar with the edge of adhesion.

RE dead spot in control range and 1000kv transformer. Good point> I have
15 or 20k hrs on Bobcats from M400/1960 to T250/2015 and know precisely
that I don't put up with dead spots, something that Bobcat was
unfortunately moving toward when I quit and Kawasaki and Cat had not
figured out last time I endured them. Hang 2000 pounds off a 6' chain on
a 40 degree slope approaching a finished fragile wall and one recognizes
right way that 'dead spot' is a double entendre. This is not a dead
spot, it is excess resistance to any attempted move away from any
previously stationary position. No transformer I know of.

Thank you for all those ideas, and the insoluble/unknowable nature of
some perhaps all software.... all good but not quite matching for some
reason or another. My tactile guess on the holdup is at the first
junction of the steering column inside the power steering unit....or if
that place is solid with no 'disjunct' there, the 'valve' or whatever
force one's hands are trying to overcome there has got an excess
pressure to overcome on one side of the valve. But that's valve talk and
may not be how that unit works at all. Flushing the system might help,
if that's possible.

If I figure it out I'll let you know.

Jim

[jame...@whidbey.com]

Eric,

I just wrote replies to the people who responded before you. Your info is the best so far even if the years aren't the same, and greatly appreciated. I'll study your explanation and will look for '16 info to see if Nissan made a running change power steering from your 13, and see if I can find more drawings. If I can't I'll let you know and would appreciate any drawings you have.

Jim

[jame...@whidbey.com]

Correction: ALL info is greatly appreciated. Eric's is giving me the best mental picture so far which is the kind of map I understand best. 

Jim