Hello! New to forum and thanks for the add!
Need help. Wife has a 2012 Nissan Rogue with 2.5l 4cyl. Throwing code p1778 stepper motor. I bought replacement. Drained fluid almost 7qts and went to installing stepper motor on valve body.
I cleaned pan sealed it all up and filled with Nissan ns2 cvt fluid. (6qts to fill line on dip). Car ran great now and no longer revs out before engaging until warm. She drove to work about an hour drive and about 45min in same problem. Revs out and does not want to engage into a higher gear. Checked code and again p1778 stepper motor code came back. I installed new part so not sure what the problem is?
Cleared code and drove for a bit till it got warm and again same code.p1778. Any help would be greatly appreciated! Thank you!

Many don't realize , this goes for virtually any code(s) retrieved - NEVER ABSOLUTELY MEANS THAT SPECIFIC PART IS BAD needing replacement. Could be upstream/downstream connections failure , or many times when the "Action" the component is supposed to do DOESN'T GET DONE which may be due to other contributory components which all may not "pull" a code. Many multiple codes are simply a result of design / software for ECM "shotguns" all problematic showings (BIG PICTURE)- yet ONE component is causing ALL .THE worst is if the actual problem is NOT a faulty component ( ie. connector loose/off) . Etc. , Etc.,Etc. AS if codes A,B,C that are "pulled" , yet something "once or twice removed" is difficult to see that it is closely related or even a sole contributory factor.
Ya best use "cross diagnostic" , second level tests , years of experience (most valuable)in addition to just first buying , especially if waiting for a shipment - man ,that case you got no excuse not to look
deeper and verify the best you can ,you know?
Definately if ya got big bucks ,or just decide to spend $$$$$$$$, and you have satisfaction of a "shiny new part" ( I didn't say it won't be defective though ) we've all Dun'nit , but keep in mind the above .

Macgiver thanks for the response. So if not stepper motor could it be solenoids in valve body? My understanding is stepper motor controls primary pulley? Correct me if wrong. Going back from that would be directly in valve body. And it only happens once warm. Could I have to much fluid? Would that cause this code? I say that because after draining and doing install. About 7qts came out. I filled back with 6 and dip stick says fluid is way high??? I’m confused with that.

Yes ,yes, # 1) Mistake I beleive , solely from anecdotal talk that abounds many forums - " I drain x amount quarts from my CVT AND find after filling it reads high " or " I only put back this much instead of the amount that came out ... "

So many people , DIY'ers , I believe half of them that beget CVT failure complaints , Limp modes , temp - hi triggered, etc.THEY ALL SAY FACTORY OVERFILLED MY CVT !!!
In those circles you'll also hear of talk of a brilliant deal on aftermarket fluid , not dealer spec NS-1 OR NS-2 ,3 whatever ,to save a "few dollars" . Those fluids that cover several specs AT ONCE CANNOT BE BETTER for the weak CVT's today , and are probably detrimental to them ,wanna gamble -Vegas anyone? Dealers mechanics say eng bay sticker is most accurate listing for what shall go into your specific car's CVT - & overrides any other reference.
My research uncovered one fact that the belts have a CRITICAL DEPTH to be SUBMERGED in the fluid for LUBE & COOLING.
Yes the higher operating temp of case components and fluid in these CVT's cause a drastically WIDE LEVEL during operation of vehicle , which I notice my level when ambient AZ temp is 112 F and running 80 mph - CVT dipstick is IN THE BENT "S" PORTION ??!!
When untouched & from the" Factory", I went & mapped out a chart per temp fluid ,also per "ticks" of temp gauge on dash , avg ambient 80 F outside , and shifting thru ea."gear" - readings of 10+ graphed levels , AS READ ON THE STICK , THE FACTORY WAS CORRECT ! Then when I changed my CVT fluid and measured VERY carefully (7 qts 5oz I believe) and little by little pouring in fresh , whilst carefully measuring and comparing my graphed observations - within 2 oz to get the EXACT LEVEL ON THE CROSSHATCH per the correct temp.
So , yeah CVT will prematurely break , yeah it'll overheat / wear more , yeah causing Limp Mode , yeah be the experience of DIY'ers who ALL have concluded THE FACTORY OVERFILLED MY CVT - " So I'll just put less back in when I change my fluid to PROLONG IT"S LIFE " ( I' m really KILLING IT !!! ).

p.s. the previous is general diagnostic philosophy , and I didn't and won't specifically give advice that I have'nt had "for sure" experience with , nor pretend to know, guess (without stating so) ,nor where there's too much "Mystery" or inherent danger in your task at hand So I have no advice on the specific inner workings , nor " how to's " the components inside CVT's.

Factory ns2 was used to refill. What other issues could I have when p1778 code is given if stepper motor was replaced?

I hope to god I never get a P1778 code.

Have to admit I was lost in this whole conversation.

No way I’ll be able to fix this code.

Probably bite the bullet and maybe let the stealership fix a issue like this.

Not liking a code like this.

Does anyone have any advice we’re to start or what might be causing this? TIA!

Can't say for sure on this one but transmissions today can have multilevel fluid levels when the trans opens a temp controlled door to fill a level even more at operating temperature. I have a Ford that you will not fill correctly unless the trans is at the correct temperature, it will appear to be overfull any other time. Underfill it cold to the mark and you tear it up at higher operating temps because not enough fluid in it.

On stepper motor, could be electrical connector issue or even TCM. Could be all working fine but the pulley slide bearings are seizing up, locking pulley from moving, that could look like a stepper issue to the computer and a common problem, the bearings there are under super load and fail rather quickly on a lot of them. Many Nissan CVT die that way. If the drained fluid was very dark an indicator there, worn metal powder in fluid.

Amc49 thank you for response! So your second paragraph. Yes when I drained fluid prior to removing valve body the fluid was terribly dark and pan had muck on it as well as metal shavings. From what your staying that is from pulley bearings and belt? P1778 being a mechanical code not electrical that would make sense even if stepper motor is good the main pulley is still not engaging properly hence the code? Am I understanding you right? Thank you again!

macgiver wrote: ↑

Sun Jun 02, 2019 12:02 pm

My research uncovered one fact that the belts have a CRITICAL DEPTH to be SUBMERGED in the fluid for LUBE & COOLING.

I think he is right, the best is to research first! Remember when I was at college, I always ignored that rule, until https://phdessay.com/category/narrative/ this service has taught me how to do. I have found here real help and so much narrative essay samples.

Codyashworth wrote: ↑

Mon Jun 03, 2019 9:54 am

Does anyone have any advice we’re to start or what might be causing this? TIA!

Hi Cody - You seem to be doing all you can and also maybe correctly. Once you change the Stepper Motor, I was told that the TCM needs to be synchronized. The TCM may also need to be reflashed. As far as I know the dealership only can do this. My 2007 Murano SE started hesitating during last winter Dec 2018 (Calgary, Alberta, Canada). This summer (4 months back) I took it to the agency pulled same P1778 code (old code sitting in the ECM/TCM). The Agency did a road test and could not replicate the problem, probably because it was summer already and the problem seems like seasonal (winter only) . They just erased the code and asked me to monitor. It is winter again, I started seeing the hesitation during cold days (-15 to -20C) when starting from cold weather. I suspect the P1778 could have come back. I have ordered a Bluetooth OBD which will arrive soon. I wil check and let you know if it has returned.

Also, I plan to take it back to the agency for another inspection and review.... Will keep you posted on what they recommend.

Cody I been having the same issue your wife’s car had. Could you help me and let me know how you were able to fix the problem. Thank you in advance.