P2731, P2722 DTC and GR6 failure, ATTESA in limp mode, now RWD only Options

[NickTO]

I'm at a track session right now and while I'm not driving anywhere hard (its cool today and the track is slippy), I got a AWD clutch overheat message and T/M system error. When it occured, I noticed the Trans Oil Pressure gauge flickered twice into the low pressure area then came back normal.The P2731 is line pressure solenoid.I pulled in, read the DTCs and there were 2x P2731 for the TCM and 1x P2731 for the ECU.I am able to clear the DTC codes.The strange thing that is happening now is that when I start the car, the T/M system check comes back with the standard:AWD system malfunction error. Visit dealer.And the AWD light in the dash is on. However there are no DTCs in the ECU to be pulled, so I'm not sure how that error occurs, if it's the same error, and why the DTC list is empty...Does anyone have a clue? Or has that happened to anyone else before?Thanks.Ps. Pardon the formatting. I'm using the mobile version of Nagtroc.

This post has been edited by NickTO: Jul 23 2009, 07:24 PM

[Caledon GTR]

The error must be in the TCM as opposed to the ECU. The Cobb system does have full communications with the TCM? Maybe the TCM forwards a error code to the ECU, which is able to be reset by the Cobb, but the originating error remains in the TCM?

[Martin Donnon]

Interesting one Nick! Pull the battery lead
Sounds like a software glitch

[NickTO]

Thanks Martin,

Unfortunately I did not have very reliable net access at the track to check up on my post. I was able to clear the DTC, but despite not having any error code, the T/M malfunction stayed on. I realized soon afterwards that the ATTESA system has somehow locked itself into limp mode; the car now runs in RWD only.

I decided to limp home from the track after making sure I had cleared the DTCs. A couple hundred feet into my journey, the ECU threw DTC code 2722 for the ECU, AWD System, T/M. The AWD light is solidly on (not as worrying as blinking), the transmission icon is flashing, and the "Service Engine Soon" light is on . The engine has new oil in it. There is also an electrical relay noise coming somewhere from the engine bay, near the firewall, when I put the transmission from N to D and stays on as long as I am driving. I figure it must be some kind of diagnostic mode that's constantly running.

The good thing is I have the entire incident on video. 17 minutes into a session, I had an AWD Clutch message warning. So I drove around the track slowly until it went away and the AWD light turned off. Incidentally, upon checking the timeline, it's very obvious that the error was occurring moments after I was turning over a crest during which the 'traction control ' light was blinking (I was in VDC-R).

2 minutes later, the AWD light turned off, the message went away.

Another 2 minutes later, another lap on, I twas taking a tight corner where the back stepped out a bit, this time a T/C Malfunction error appeared. At that point I just pulled off the line, slowed down completely and headed back to the pits (I was at turn 3 or 20). 30 seconds into this, I changed the MFD to a display that shows Transmission oil pressure. It was at 0, but fluctuated back to normal. Not sure if that's due to a diagnostic program running and using the CAN Bus so the data couldn't be retrieved or if it's symptomatic of DTC 2731 For the remainder of the slow lap, the Transmission oil pressure can be seen flickering momentarily into the '0' area and back.

In any case. The car appears fine, but the AWD system is bonkers. I can clear all the codes and the car turns to "ON" without any error. As soon as I fired up the engine, the dash lights up like a Christmas tree.

[Martin Donnon]

I have seen this before Nick, on some of the competition cars here on undulating fast roads.
Have you disconnected the battery for five minutes then tried it?

[NickTO]

Unfortunately, disconnecting the battery only clears the DTC. But the P2722 code comes right back as soon as the engine is fired up. After a couple start/stop sequences the 'service engine soon' lights up as well.Going to the dealer so they can look at it...There's a funny electrical noise in the engine bay as well.

This post has been edited by NickTO: Jul 15 2009, 01:04 PM

[yano]

Unfortunately, disconnecting the battery only clears the DTC. But the P2722 code comes right back as soon as the engine is fired up. After a couple start/stop sequences the 'service engine soon' lights up as well.Going to the dealer so they can look at it...There's a funny electrical noise in the engine bay as well.

damn Nick I hope it's nothing major

[NickTO]

damn Nick I hope it's nothing major

Well... I took the car in this afternoon.

The car is spending the night at the dealer, and I suspect a couple more days. The master tech was able to validate my diagnosis: The car will not clear the error code, the AWD system is in limp mode and stuck in RWD, there is a T/M, AWD and Engine malfunction light in the dashboard and there is a strange solenoid-like noise coming from under the car when going from N to D and then applying throttle.

The error code P2722 is from the "Lubricating flow solenoid valve", the description of which is:

• The lubricating flow solenoid valve is installed on the front control module and controls the lubricating flow of the clutches A and B with the signals from TCM. This subsequently controls the lubricating flow of the gear train.
• The lubricating flow solenoid valve is a N/H type (normal high) in which control oil pressure is built up when no current flows through the coil.

Unfortunately, beyond doing a diagnostic (done today), and confirming that the DTC doesn't go away, the solution is to "Repair or replace damaged part"... which is buried in the GR6...

So I have some apprehension about where this might be going.

Other than all those errors, the car drove normally. Transmission Oil pressure and temperature were nominal and all the gears worked as normal.

This post has been edited by NickTO: Jul 15 2009, 08:11 PM

[MC]

nick, anyway in hell it might be related to that sound you can i had in 1st?

[nbgtr]

Well... I took the car in this afternoon.

The car is spending the night at the dealer, and I suspect a couple more days. The master tech was able to validate my diagnosis: The car will not clear the error code, the AWD system is in limp mode and stuck in RWD, there is a T/M, AWD and Engine malfunction light in the dashboard and there is a strange solenoid-like noise coming from under the car when going from N to D and then applying throttle.

The error code P2722 is from the "Lubricating flow solenoid valve", the description of which is:

• The lubricating flow solenoid valve is installed on the front control module and controls the lubricating flow of the clutches A and B with the signals from TCM. This subsequently controls the lubricating flow of the gear train.
• The lubricating flow solenoid valve is a N/H type (normal high) in which control oil pressure is built up when no current flows through the coil.

Unfortunately, beyond doing a diagnostic (done today), and confirming that the DTC doesn't go away, the solution is to "Repair or replace damaged part"... which is buried in the GR6...

So I have some apprehension about where this might be going.

Other than all those errors, the car drove normally. Transmission Oil pressure and temperature were nominal and all the gears worked as normal.

Fingers crossed Nick!

Hope its nothing major.

Wish you good luck!

[NickTO]

nick, anyway in hell it might be related to that sound you can i had in 1st?

I doubt it. This appears to be an electrical issue, or a solenoid malfunction.

I think today, day 3, is playing out like a "CSI Tennessee" episode with my car on a hoist...

This post has been edited by NickTO: Jul 17 2009, 08:32 AM

[Martin Donnon]

I dealt with a company here that had an R35 with an eletrical AWD problem similar to yours Nick. I will get onto it and track down the fix for you....

[vincemims]

I'm at a track session right now and while I'm not driving anywhere hard (its cool today and the track is slippy), I got a AWD clutch overheat message and T/M system error. When it occured, I noticed the Trans Oil Pressure gauge flickered twice into the low pressure area then came back normal.The P2731 is line pressure solenoid.I pulled in, read the DTCs and there were 2x P2731 for the TCM and 1x P2731 for the ECU.I am able to clear the DTC codes.The strange thing that is happening now is that when I start the car, the T/M system check comes back with the standard:AWD system malfunction error. Visit dealer.And the AWD light in the dash is on. However there are no DTCs in the ECU to be pulled, so I'm not sure how that error occurs, if it's the same error, and why the DTC list is empty...Does anyone have a clue? Or has that happened to anyone else before?Thanks.Ps. Pardon the formatting. I'm using the mobile version of Nagtroc.

Hey brother. My car was giving me everyone of these codes and acting just like yours with some major track times. Now it only only did it once as complete as you described having to take it into the dealer. Here is what I found out. I could clear the codes with the cobb like you, but it stores info in the black box that only the Nissan tecs (not the dealer) can "hack into" via the computer on line. What they my dealer had to do was to plug it in to get the Nissan "geeks" to clear the code and get it back to normal and clear all the codes. It was not big deal other than a pain in my butt, and all went back to normal soon. They said it was a computer glitch from the car "loosing traction to many times throwing it into fail safe mode." They could make sure all was normal and ok.
Hope this is all it is for you. Please let us know.
Vince

[NickTO]

Hey brother. My car was giving me everyone of these codes and acting just like yours with some major track times. Now it only only did it once as complete as you described having to take it into the dealer. Here is what I found out. I could clear the codes with the cobb like you, but it stores info in the black box that only the Nissan tecs (not the dealer) can "hack into" via the computer on line. What they my dealer had to do was to plug it in to get the Nissan "geeks" to clear the code and get it back to normal and clear all the codes. It was not big deal other than a pain in my butt, and all went back to normal soon. They said it was a computer glitch from the car "loosing traction to many times throwing it into fail safe mode." They could make sure all was normal and ok.
Hope this is all it is for you. Please let us know.
Vince

Vince, well that sounds encouraging. I have the perfect video evidence of my car drifting to the left on a right hand turn over a blind crest, the VDC light (the car with the slipping lines) flashing in the dash while the car is drifting and KAPOW! the dash lighting up 2 seconds later.

Your description does sound exactly like what I have. Initially, I was dumbfounded that I could clear the DTC, but the AWD light stayed on; obviously a sign that there was something deeper than the ECU storing the DTC permanently. Then the P2722 that kept coming back and the AWD putting itself in RWD only (Self preservation I suppose!).

If you don't mind, would you be willing to share more info over PM on how it got resolved, or how long your car was in? Mine's going on for 3 days + the upcoming weekend, so I have to think that Nissan Canada has not seen this issue before but NNA might have.

[NickTO]

I dealt with a company here that had an R35 with an eletrical AWD problem similar to yours Nick. I will get onto it and track down the fix for you....

Thanks Martin, I think I heard of this back when it happened. Was it a superlap time attack with one of the first JDM GT-Rs privately tested in Australia?

[Martin Donnon]

Could well have been Nick!
Note to self - Nick does not miss much

[Martin Donnon]

Ok Nick I did some research on this problem for you this morning. The Aussie car that threw the same error actually had a pinched wire in the loom that runs through to the front section of the gearbox that caused the solenoid in question to short to ground, and start the same buzzing and errors that you are having. Once the wire was repaired the car worked faultlessly. Hope this helps

[NickTO]

Ok Nick I did some research on this problem for you this morning. The Aussie car that threw the same error actually had a pinched wire in the loom that runs through to the front section of the gearbox that caused the solenoid in question to short to ground, and start the same buzzing and errors that you are having. Once the wire was repaired the car worked faultlessly. Hope this helps

That's a fantastic bit of info.

Many thanks to you Martin for your help and convey my appreciation to your source as well.

[celsius]

That's a fantastic bit of info.

Many thanks to you Martin for your help and convey my appreciation to your source as well.

Nick, hope your gets fixed...any news from NissaN?

[NickTO]

Nick, hope your gets fixed...any news from NissaN?

'nuff said

This post has been edited by NickTO: Jul 22 2009, 09:24 AM