# Help with 09 Maxima



## Maximum trouble (Dec 9, 2021)

I have driven other 09 nissan maxima 
And I know something is wrong with my 09 maxima that I got 9 months ago.
It seems to shift way to early, 
I can be going 20mph and the transmission is in 5th speed.

I know this because I can shift down and see what gear I am in.

If I manually shift the car in semi-automatic mode I can shift it how it should be.

The transmission is strong no slip no codes.

I asked a dealer and didn't get far


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## VStar650CL (Nov 12, 2020)

When you say "no codes", is your scanner capable of reading the TCM? Most cheap scanners can only read the engine, and a tranny issue may not cause any codes in the ECM.


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## rogoman (Dec 16, 2004)

Maximum trouble said:


> I have driven other 09 nissan maxima
> And I know something is wrong with my 09 maxima that I got 9 months ago.
> It seems to shift way to early,
> I can be going 20mph and the transmission is in 5th speed.
> ...


Your transmission is a CVT which does not shift like standard A/T's. There is most likely one or more DTCs set. To read them requires a more advanced scan tool.

From the symptoms you're describing, a problem with the "stepping motor" may be causing the symptom. A DTC should verify this.

The stepping motor connects to a ratio control arm and ratio control valve. The other end of the ratio control arm connects to the pulley follower. The main purpose of the ratio control valve is just as its name implies: to change the ratio of the transmission. It does this by changing the pressure in the pulleys. The transmission control module sends a signal to the stepper motor in a certain pattern. To keep it simple, the stepper motor can extend or retract, moving the position of the ratio control valve.


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## Maximum trouble (Dec 9, 2021)

Thanks for the clarification,
yes it is no codes with a cheap scanner.


rogoman said:


> Your transmission is a CVT which does not shift like standard A/T's. There is most likely one or more DTCs set. To read them requires a more advanced scan tool.
> 
> From the symptoms you're describing, a problem with the "stepping motor" may be causing the symptom. A DTC should verify this.
> 
> ...


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## Maximum trouble (Dec 9, 2021)

Thank you!!!!
Finally something that makes sense. 

Don't think I can get thru Nissan because I would have to buy the whole valve body $$$

Protrans I heard I can get a stepper motor .
Do you know where I could get one?


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## rogoman (Dec 16, 2004)

You can buy CVT stepper motors from Amazon for around $30. Just verify with a DTC code that it's a stepper motor failure.


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## Maximum trouble (Dec 9, 2021)

I know I have to get the Dtc scanned.
But I have not been able to get that done.
And I figured that the step motor was a rare item cheap enough might as well just replace it.

I did that and I still have the same condition

In the regular automatic mode the car drives okay but it seems to goes into high speed too soon.
And I know that because I could be going 20 miles an hour and in semi-automatic mode I downshift and can see what gear I was in.

The car starts out in first gear but just goes through the gears too quick.

If I shift it with semi-automatic ,
I can shift the car the correct way.
And when I do this it shifts smooth.

It actually shift smooth all the time I don't feel any slipping except for when I'm in 5th gear going 20 or 30 mph and I think the torque converter allows the slippage.
And I get to a certain speed and I can tell the torque converter locks up

It's almost like I just need it calibrated or little bit adjusted.

I was thinking of the secondary pressure sensor, anyone's thoughts

I seen the scenario with the stepper motor goes bad and gets stuck in last year and cannot crest a hill which is not my situation

And I cannot find anything on this


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## Maximum trouble (Dec 9, 2021)

I had the tcm scanned and showed no codes.
Any thoughts


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