No, you need to get the IP Char data from the new VB loaded into your TCM. The TCM is trying to run the tranny with data from your old VB. Sometimes they work that way (like yours), but they rarely work well. If you have the CVTz50 app then I heard there's a trick you can do to get the data to load DIY, otherwise you'll need a trip to the dealer.
Codes and issues after valve body replacement
So I had 2 codes, 1 for stepper motor, 1 for solonoid a. So I got a valve body from Amazon. After install I'm getting different codes and it's really really laggy to accelerate. And after driving on the highway for a few minutes it gets stuck in 7th and slowly slows down and loses power. Do I need to use the harness from my original valve body?
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What if I boost take the solenoids and stepper motor of the new vb and put it on the old?No, you need to get the IP Char data from the new VB loaded into your TCM. The TCM is trying to run the tranny with data from your old VB. Sometimes they work that way (like yours), but they rarely work well. If you have the CVTz50 app then I heard there's a trick you can do to get the data to load DIY, otherwise you'll need a trip to the dealer.
Might work, but you could be up a real s#!t's creek if it doesn't. I'm pretty sure the solenoids are calibrated in situ at the factory, which means they're calibrating for all the characteristics, electrical and mechanical and hydraulic. So if it doesn't work, you might simply wind up with two VB's that are both unusable because the calibrations have become unknowable.
What's actually different about the vb? Just the electronics?Might work, but you could be up a real s#!t's creek if it doesn't. I'm pretty sure the solenoids are calibrated in situ at the factory, which means they're calibrating for all the characteristics, electrical and mechanical and hydraulic. So if it doesn't work, you might simply wind up with two VB's that are both unusable because the calibrations have become unknowable.
And is it possible the bad stepper motor caused the code for the solenoid a on the stock vb? They all click when I put 12 volts to themMight work, but you could be up a real s#!t's creek if it doesn't. I'm pretty sure the solenoids are calibrated in situ at the factory, which means they're calibrating for all the characteristics, electrical and mechanical and hydraulic. So if it doesn't work, you might simply wind up with two VB's that are both unusable because the calibrations have become unknowable.
Depends on whether the code was a performance code or a hard code. Hard codes will point to an electrical failure, performance codes can be hydraulic or mechanical and need to be sorted out.
P1778 p0746
Those are codes I had before the valve bodyDepends on whether the code was a performance code or a hard code. Hard codes will point to an electrical failure, performance codes can be hydraulic or mechanical and need to be sorted out.
Both of those are performance codes and not hard codes, and together they probably indicate belt slip. The P0746 may also indicate low line pressure. The '10A TCM firmware lacks any judder detection, so a line pressure test and belt inspection is the only way to sort that out. Try getting the correct IP Chars loaded and see if any codes return, if they do then the tranny has problems bigger than just a VB. There was probably never anything wrong with your stepper.
So I think I got the wrong valve body possible.how can I verify? And it didn't come with the CD or info to program it. One thing I noticed is my original one has a plug where the new one has a sensor, I switched them before installing.Both of those are performance codes and not hard codes, and together they probably indicate belt slip. The P0746 may also indicate low line pressure. The '10A TCM firmware lacks any judder detection, so a line pressure test and belt inspection is the only way to sort that out. Try getting the correct IP Chars loaded and see if any codes return, if they do then the tranny has problems bigger than just a VB. There was probably never anything wrong with your stepper.
If there are no markings on the new VB then I don't know any way to identify it, the '10A VB's all look pretty much the same. There won't be programming info because on '10A's it's stored in the VB on an EEPROM, you just need to put the TCM into a special mode to erase the old data and read the new VB.
We used the snap on scanner to clear the calibration or whatever and go drive it but nothing changed. I checked the old stepper motor and the ohms are within spec. The one solenoids all click but I don't know if that means there good?If there are no markings on the new VB then I don't know any way to identify it, the '10A VB's all look pretty much the same. There won't be programming info because on '10A's it's stored in the VB on an EEPROM, you just need to put the TCM into a special mode to erase the old data and read the new VB.
There's a specific process used for reinitializing the VB, the only thing most scanners can clear is deterioration. Even with a capable scanner, there's a specific procedure which needs to be followed to put the TCM in erase/read mode. Here's the FSM for an '08 gen4 Altie with a '10A trans:
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What scanners are capable of this? He has an autel and snap on. The snap on made the calibrating say 0. Before changing the vb it wound rev and little then slam hard like you let the clutch out then it wouldn't wanna go. After changing the vb its smooth but really laggy. Would the vb itself have been the issue or the solenoidThere's a specific process used for reinitializing the VB, the only thing most scanners can clear is deterioration. Even with a capable scanner, there's a specific procedure which needs to be followed to put the TCM in erase/read mode. Here's the FSM for an '08 gen4 Altie with a '10A trans:
View attachment 11700 View attachment 11701
If it smoothed out after the SnapOn then it took the recalibration, that bangy stuff is usually what happens when the IP's are wrong. If you mean laggy acceleration, that could be an engine issue and not the tranny. If you mean laggy going in and out of gear, then it probably has a pump pressure issue, the VB won't fix that.
No I meant before I change the valve body at all it was slipping and banging. After I changed it it was smooth but really slow like I'm not even pressing the throttleIf it smoothed out after the SnapOn then it took the recalibration, that bangy stuff is usually what happens when the IP's are wrong. If you mean laggy acceleration, that could be an engine issue and not the tranny. If you mean laggy going in and out of gear, then it probably has a pump pressure issue, the VB won't fix that.
The one that starts with h is the original, j is the new one. Could this be the issue?No I meant before I change the valve body at all it was slipping and banging. After I changed it it was smooth but really slow like I'm not even pressing the throttle
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Those are manufacturer's marks and not Nissan ones, so I can't tell you what they mean. But if you installed a wrong VB, that could obviously cause all sorts of issues.
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