k4uwc

I've been reading a lot about these error codes from a 2007 Maxima and about Nissan CVTs in general. I bought the vehicle and the person said it wouldn't "shift into high gear" however when we test drove it it was fine. I've had it for a week and cannot get it to duplicate the problem however the codes in the transmission are telling me some bad news.

I dropped the pan today and it looked good. No metal pieces but just dirty oil and some sludge around the magnet. Of course the previous owner may have just cleaned it out but it sure didn't look like that pan had been off in a while.

The vehicle has about 175k miles.

I'm soliciting input from you on what you'd do next. I know it's hard to diagnose via the Internet but my guess is to install a new valve body. Or would you start with just the stepper motor and fresh NS-2 fluid and see what happens?

As a back-up plan I jsut parted out a 2008 Maxima so I kept the transmission. I have no reason to believe it's bad so I could pull parts from it or install it if any minor repairs to this transmission don't clear the codes.

k4uwc

Costee

Since the car is showing no signs of the expected symptoms, I'd suggest you delete the codes and keep watch. I'm suspecting the step motor. The other two codes are virtually the same and probably triggered by the step motor. Should the symptoms recur and matched with the codes then you could replace the valve body with the one in the spare 2008 transmission you have. Putting in the spare transmission altogether is yet a further option. Your situation is certainly not dire, happily.

k4uwc

I'm following up on my post.

I put in a reman valve body from Suncoast valve bodies. They do Youtube videos and seemed like nice and knowledgeable folks. Of course it's very hard for them to diagnose my problem but a new valve body seemed logical.

Unfortunately, the new valve body yielded no improvement. The car won't "shift" and had high RPMS as speed increases. 3k rpm at 50 mph and then it'll go as high as you want until redline. I manually tried to go to "5" but it made no difference.

So what do you think is a good next step? I have a 2008 parts car so I'm thinking about trying to swap the TCM just to see what happens.

One problem is that even after having the battery unhooked for a few days the TCM still shows the same codes. It never reset and my OBDLink can't clear those transmission codes so I don't know what's going on right now after the valve body change.

Suggestions?

I ran into this and this is exactly my problem, including the tire pressure light.

https://certifiedtransmission.wordpr...an-maxima-cvt/

k4uwc

replying again... still don't have "overdrive" on the CVT. I know... it doesn't have OD but the RPMs are high and acts like it isn't shifting

I took out the ABS fuse to test if the sensors were feeding bad speed data to the computer. It may have made a little difference but not much.

I'm still hoping to hear from you of you out there on what you'd recommend. try the valve body from the other transmission or start looking into other sensors that may be causing the transmission to not "lock up". Also, could this be indicative of low fluid pressure in the transmission?

Akramer

Did you ever find a solution to the problem? This is the only post ive found that describes my problems perfectly, did a new tcm fix anything?

k4uwc

No. Not yet. Thanks for checking back as most threads die out. I put a new valve body and stepper motor into the transmission and that didn't help. I have a parts car (2008) so a free test is to take the ABS sensors and move them over to the 2007 and see if that helps. I doubt it will as I looked at the sensors on the rear wheels of the 2007 and they were fine. Came out no problem. No rust buildup. However the car will activate the ABS prematurely when I back out of my driveway so that's a good clue something is amiss.

I'll report back if the sensors help. If you have any suggestions then let me know! I hate throwing new parts at it but I'm OK to waste my labor to install use parts.

Akramer

damn, and you already replaced the maf sensor like the guy in that post? I did but now im trying a tcm

rafael.a.lopez76

I was wondering if you solved your issue with your Maxima. I have Nissan Maxima same here same codes same symptoms.

k4uwc

No change. I haven't worked on it in several months. I pulled the wheel sensors off a 2008 and thought I may try them just because it's free. I expect it will not change anything. I have a CVT waiting to put in so if the ABS sensors don't change anything I'll just do the work to put in the transmission and then see what happens.

Keep us informed of what you find. I hate to put in a CVT after reading others who solved their problems with rear hubs or something non-transmission. I have taken out the sensors in my car and non were rusty or looked suspicious like they would be a cause for concern.

TDGrant

I had issues with my ABS sensors because of water(ice)/rust. However, unlike you, I did not have any CVT codes, so I suspect, as you have alluded to, that your issue is not not because of your ABS sensors.

TDGrant

Reference P1778.

https://www.my4dsc.com/p1778-nissan-...re0f10e-jatco/

japonicadunbar

I don't have any codes, but I don't hear any shifting of gears until I reach about 60mph. Just wondering if it is the tranny and not the D step.