V9X low range auto issue.

[Don-vic]

I know this has been mentioned on old posts but would like to know if there has been any recent developments regarding this issue ?
To my "uneducated" mind, it would seem to be an easily fixable problem for someone in the auto transmission game. I remember someone outlining a possible method of manually switching off the "upshift" when in low range. Has anyone out there pursued this method ?

 

[Old.Tony]

RaptorThumper developed a method (here's the first post) of engaging 4LO without the ECU being aware of it (basicaly, manually driving the change servo). Nothing has happened since, and nothing will likely ever happen. Nissan have moved on, the 8-speed auto box will be what they're focusing on.

 

[djverrall]

Hi guys i also have had bulk dramas for ages on my 550 with 4lo only when selecting manual mode it doesnt hold gears in it upshifts by itself erratic. But when in 4 hi manual mode works fine and you can hold the gear that you want it in very frustratin frustrating when 4wding in the sand . Does anyone have a fix for this ?

 

[djverrall]

anyone ? i tried my mates the same as mine but its acts normal the way it should only diff he has slightly diff size wheels dont think this would make a diff

 

[Old.Tony]

I doubt tyre/wheel size would make any difference at all - the car would be completely unaware that the tyres/wheels are any different as long as they all match, the car rotates the drive shafts and the ABS sensors confirm that rotation is happening - end of story.

If your mate has a 5-speed auto that will explain the difference. The issue occurs with the RE7R01B and not the RE5R05A box.

 

[djverrall]

nah he has the 7 speed auto same as mine i just thought wheels size may of given off different ground speeds for speed for wheel speed semsors.



starting to become very frustrating cause its useless in the sand

 

[Old.Tony]

The vehicle doesn't actually know what the ground speed really is. It only knows that there are a certain number of rotations of the wheel occuring in a given amount of time resulting in (based on a specific wheel circumference) a very close measure of speed and distance.

Raptorthumper's fix will remedy it.

 

[djverrall]

hi guys i have implemented the mod switching the actuator manualy with mom dpdt switch on dash setting it up now so i can revert back to standard switch to select 4 high of factory switch with diodes inline from trans ecm. will keep everyone in the loop to see how it goes .

 

[djverrall]

hi guys i have implemented the mod switching the actuator manualy with mom dpdt switch on dash setting it up now so i can revert back to standard switch to select 4 high of factory switch with diodes inline from trans ecm. will keep everyone in the loop to see how it goes .

re edit i have just fitted a 2 pole switch to join existing wires back to factory when not using 4 lo momenty switch.

 

[nuthanav]

Hi djverral,
I'm interested in your work on this. I'm no electronics person so forgive me if I've got your post all wrong but are you trying to get control of the trans ecu to hold gears in 4Lo through the factory 4WD switch along with a switch to isolate the factory 4WD Lo congtrol logic as Raptorthumper has in his work around mod?

 

[landmannnn]

My 2014 V9X doesn't show these symptoms. 4Lo it hangs onto first even against the red line.

 

[raptorthumper]

That's interesting to know. Maybe the UK versions have different transmission calibration. Like to confirm this with another UK V9X owner though.


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[landmannnn]

You would wonder why they would, but maybe when they gave the job to a junior to delete the DPF he had a play with the coding.

 

[Matthew Stevens]

Hi guys,

Has there been any development on this as I have experienced this for the first time and it's not something i'd like to experience again. Anyone know of a fix? Thanks.