[Cryogenix1]

I would at least try disconnecting the NEG wire to the battery, reconnecting it, firing up the car to see what happens. That's solved a lot of glitches on my 2003 and 2021. If it's just sitting there, might as well try a few easy things.

 

[Pilgrim]

I would at least try disconnecting the NEG wire to the battery, reconnecting it, firing up the car to see what happens. That's solved a lot of glitches on my 2003 and 2021. If it's just sitting there, might as well try a few easy things.

Absolutely!!!

 

[Cryogenix1]

And I might also shift through the drive selections aggressively multiple times to possibly shake the CVT back to life. But, really, I would also try that...

I'd probably also drop in a quart of CVT fluid, just in case. I overfilled my 2003 CVT and it took a lot to do it. I think 4-5 quarts.

 

[160256]

I would at least try disconnecting the NEG wire to the battery, reconnecting it, firing up the car to see what happens. That's solved a lot of glitches on my 2003 and 2021. If it's just sitting there, might as well try a few easy things.

Trying to create a "Frankenstein" Murano? LOL I'll play around with it this weekend when I'm off. Thanks for the tips, keep 'em coming

 

[160256]

And I might also shift through the drive selections aggressively multiple times to possibly shake the CVT back to life. But, really, I would also try that...

I'd probably also drop in a quart of CVT fluid, just in case. I overfilled my 2003 CVT and it took a lot to do it. I think 4-5 quarts.

Well, I just tried your suggestion of disconnecting the neg battery terminal for a bit and reconnected it. Now the car won't rev up (rpm) past the 1. I floored the pedal and it won't go all the way to 8 like before (last night) when I tested it. Also I ran the diagnostic code on the app and it's now throwing up these 3 codes

 

[Cryogenix1]

It sounds like your car is still in limp mode, for whatever reason. The codes you showed are "pending," which I believe means that aren't actually the cause of anything happening, but they were suspected of being a problem while the car was running. I think they have to trigger twice or for a certain duration before the ECM/TCM locks them as a true DTC. Is your check engine light on? If so, maybe they are real trouble codes, or perhaps the CEL is due to codes in the TCM that need to be read.

Just disconnecting the NEG shouldn't have caused limp mode. I'm guessing the act of eliminating power flushed something out of "memory" and made it start from scratch, where now different parameters are being set that maybe are more accurate to whatever problem your car has. The only advice I would offer is make sure the battery is fully charged and the alternator is working and try again. And maybe download the beta CVTz50 to see if there are codes in the TCM.

 

[160256]

It sounds like your car is still in limp mode, for whatever reason. The codes you showed are "pending," which I believe means that aren't actually the cause of anything happening, but they were suspected of being a problem while the car was running. I think they have to trigger twice or for a certain duration before the ECM/TCM locks them as a true DTC. Is your check engine light on? If so, maybe they are real trouble codes, or perhaps the CEL is due to codes in the TCM that need to be read.

Just disconnecting the NEG shouldn't have caused limp mode. I'm guessing the act of eliminating power flushed something out of "memory" and made it start from scratch, where now different parameters are being set that maybe are more accurate to whatever problem your car has. The only advice I would offer is make sure the battery is fully charged and the alternator is working and try again. And maybe download the beta CVTz50 to see if there are codes in the TCM.
[/Q

Yes, the check engine light is on which is why I rant the diagnostic code test on the car app. What is the TCM in CVTz50?

 

[Cryogenix1]

Generally speaking, any scan tool can read codes from the ECM/ECU (Engine Control Module), but most can't read codes stored in the TCM (Transmission Control Module) of the CVT, so your check engine light could be related to trouble codes stored in the ECM or the TCM, but if you don't have the correct scan tool or app (such as CVTz50) you'll never know what may be wrong with the CVT. And when I had CVT trouble, the Check Engine Light never came on, nor did the CVT light (in my 2003). I'm not sure if that ever changed or if my car had a glitch.

I don't know if Torque Pro can pull codes from the TCM. I think a few members here use that.

 

[160256]

Generally speaking, any scan tool can read codes from the ECM/ECU (Engine Control Module), but most can't read codes stored in the TCM (Transmission Control Module) of the CVT, so your check engine light could be related to trouble codes stored in the ECM or the TCM, but if you don't have the correct scan tool or app (such as CVTz50) you'll never know what may be wrong with the CVT. And when I had CVT trouble, the Check Engine Light never came on, nor did the CVT light (in my 2003). I'm not sure if that ever changed or if my car had a glitch.

I don't know if Torque Pro can pull codes from the TCM. I think a few members here use that.

I ran the app and took some screenshots. Can you direct me on where/what to do? Thanks

 

[Cryogenix1]

And you can tap the three dots in the top-right to see other options and decide what things you want to monitor.

I don't have any codes in my 2021, so I have to draw from memory using it on my 2003.

Once the app is connected, at the main function screen...

- CVT Data monitor - tap the button to connect - if there is a yellow box or a red box (or both) where the clock usually is, press that boxed area and you'll be taken to the trouble codes section.

OR

- Read/clear CVT DTC - tap this button to read CVT codes, if there are any.

- Read/clear engine DTC - tap this button to read CVT codes, if there are any.

I don't recall where I used to see the last five inactive (pending) trouble codes. It may have been at the start-up screen when the app is connecting, but I'm not sure. Maybe try the CVT information button.

Here are two snaps from my 2003 AWD...

No trouble codes...

A CVT trouble code(s) is stored...

 

[160256]

And you can tap the three dots in the top-right to see other options and decide what things you want to monitor.

I don't have any codes in my 2021, so I have to draw from memory using it on my 2003.

Once the app is connected, at the main function screen...

- CVT Data monitor - tap the button to connect - if there is a yellow box or a red box (or both) where the clock usually is, press that boxed area and you'll be taken to the trouble codes section.

OR

- Read/clear CVT DTC - tap this button to read CVT codes, if there are any.

- Read/clear engine DTC - tap this button to read CVT codes, if there are any.

I don't recall where I used to see the last five inactive (pending) trouble codes. It may have been at the start-up screen when the app is connecting, but I'm not sure. Maybe try the CVT information button.

Here are two snaps from my 2003 AWD...

No trouble codes...
View attachment 59588

A CVT trouble code(s) is stored...
View attachment 59587

Thanks. I was able to run through each option and these were the results. I see it has added another error code on this app so now it's 4 total.

 

[Cryogenix1]

I just noticed you said prior to this problem you had to use a screwdriver on the shift-lock to shift. That combined with everything else could easily still point to a battery/charging issue. Lack of power or intermittent power can cause a slew of problems for the Murano CVT. I don't think there's an easy or clear answer.

Replace the valve body? If the battery and charging system are having issues, you should still have the same problem.

 

[160256]

I just noticed you said prior to this problem you had to use a screwdriver on the shift-lock to shift. That combined with everything else could easily still point to a battery/charging issue. Lack of power or intermittent power can cause a slew of problems for the Murano CVT. I don't think there's an easy or clear answer.

Replace the valve body? If the battery and charging system are having issues, you should still have the same problem.

If the battery was bad wouldn't the car not start or run at all? I guess when the shop gets it next week they will have a slew of problems to combat. I'm looking at cars just in case so as of right now I'm considering it DOA. I did notice while the car is running all the instrument lights on the vehicle flicker continuously while running but this has been going on for a long time.

 

[Cryogenix1]

It all depends... If the battery has enough juice to keep the engine running but not enough (due to a charging issue) to also make the CVT and support components operate, you might be stuck in limp mode. It's also possible you have random satisfactory charging. The problem with the battery/charging scenario is, if either of those is really dying, you should be getting some dummy lights to indicate it.

The headlights on my 2003 flickered a bit, but never the gauges. That might mean you have some bad grounding points or a loose wire or malfunctioning voltage regulator, etc. It's possible that any of those problems might not trigger the appropriate dummy lights.

 

[160256]

It all depends... If the battery has enough juice to keep the engine running but not enough (due to a charging issue) to also make the CVT and support components operate, you might be stuck in limp mode. It's also possible you have random satisfactory charging. The problem with the battery/charging scenario is, if either of those is really dying, you should be getting some dummy lights to indicate it.

The headlights on my 2003 flickered a bit, but never the gauges. That might mean you have some bad grounding points or a loose wire or malfunctioning voltage regulator, etc. It's possible that any of those problems might not trigger the appropriate dummy lights.

My question to you is do I take it to a mechanic shop or a transmission shop? The place I plan on taking it to is just a transmission shop since that was what was relayed to me. I really wish I could get a mobile mechanic to come look at it.

 

[Jim Morris]

The throttle body cannot cause the transmission to slip but the valve body sure can. Put the transmission shift lever in the "N" position then push it to the left towards driver, and pull it back into the manual shift position. If the car will move in the manual shift position, the valve body is fouled. Most early model Nissans and other car makes up through 2018 suffer CVT failure at less than 80k miles. (<Moderator note: this is NOT TRUE.) There is a lawsuit settlement that covers the cost of repair/replacement if the mileage is within the listed range. I would not waste my money buying a used CVT. Do yourself a favor and get the transmission rebuilt by a dealership or by a reputable transmission repair shop with a written nation wide mileage warranty guarantee. (<Moderator note: most dealerships DO NOT rebuild Nissan CVTs, and almost no independent shops do.) CVT transmissions must be properly flushed and have new oil installed every 40,000 - 60,000 miles depending on OEM recommendations. I wonder if the Nissan Pathfinder non-CVT transmissions could be adapted to install in a Murano as they are good for over 200k miles of service.

 

[Pilgrim]

Moderator note: the above post was not deleted but I felt it necessary to point out some false or misleading statements. Take this post with a grain of salt.

 

[160256]

Moderator note: the above post was not deleted but I felt it necessary to point out some false or misleading statements. Take this post with a grain of salt.

Thanks for the help over the years. I'm officially no longer a MO owner but will cherish the past 13 years and memories.