G35 coupe auto transmission light flashing
 

Hey everyone, i had purchased an 05 g35 coupe about a month ago, and am new to this community. I am looking for some advice on what i am experiencing. Yesterday i was driving the car and with it in sporttronic shift and i was down-shifting to a traffic light. I got to 1st and it didnt free rev going down to 1st from 4th as it usually does. I came to a stop at the light and put it back over to auto. I pulled away from the traffic light and the car felt like it was in 3rd or 4th gear. I put it over to sporttronic and it was in 4th. I tried to put it down to 1st and it showed it would go down to 1st put the car was still in 4th gear. I pulled over and turned it off. Started it back up and the a/t light flashed for ~10 seconds. The car is fine in reverse but once you put it in drive it bangs hard and starts off in 3rd or 4th gear. I didnt pull any codes yet as im looking for some advice if anyone else experienced this or knows any info on trans concerns. I've read online that it could be the tcm, or the valve boddy inside the trans. Im considering taking it to the dealer to have them check it out but i figured i would ask all of you first. Any info is greatly helpful and appreciated.

Did you check the fluid level for the ATF? Being low on fluid can make the trans shift very harshly.

No I have not checked the fluid yet in the trans. I was thinking it would be something more severe then that...?

I'd check the level of the ATF fluid first. Fluid should be red. If it is dark black and smells burnt then you may have issues. To check the fluid take off the engine cover and look toward the back of the motor for the ATF dipstick. Use a socket to remove the bolt holding the ATF dipstick down. Measure the fluid with the engine running (preferably at running temp) and the trans in park. (SEE SERVICE MANUAL for detailed procedure, i'm just writing from memory)

Then check the code via a OBII scanner. How many miles on the drivetrain? Has the AT ever been serviced by previous owner?

The car has 124K on it. I purchased it from a guy who bought it with 117k on it. He had a daily driver and used this for weekends. The guy he got it from was the ORIG. owner. Clean carfax. and the orig. owner had it from late 2004- late 2011. Not sure on any maint. But the guy I got it from only ran 93+ fuel and full syn oil. and he said that the person he got it from was religious with maint. So I would assume? but then again out of sight out of mind..... I parked the car at my garage about an hour away from where I live and picked up my 4x4 since here in PA we are getting so much snow. So i'll prob. head up this weekend at least to get the code pulled with my scanner so I can post for more info for you all.

You and I have pretty similar mileage. I've had my 06 since it has had 20k miles so I have done all the maintenance myself. For comparison, I did drain and fill of the ATF at 60k, 90k and 120k. Hopefully the previous owner did one around 60k and 90k. That said, there are plenty of people that have never changed it at 100k miles and it stills shifts fine. Good luck in the snow. It's 82 in sunny FL here today.

The 5AT trans in this car has proven to be reliable. Issues seen have been mostly valve body issues with the shuddering during lockup at 40mph, but that issue normally present early on in the car's life.

That should be the ATF fluid level. I had the same problem and it was because I was low on ATF fluid.

I have not had anytime to head up to the garage where the car currently is. I do plan on going up this weekend to try and figure out what the concern is with the trans. My question is; would low fluid cause what I had experienced all of a sudden with the trans feeling like it was put into a limp mode? sabino787: Is this exactly what you had experienced when you found your 35 was just low on fluid?? Also, I have a nissan dealer close by that I can purcahse a qt or two of trans fluid from (350z fluid) would this be ok to run in the g35 or should I go to an infiniti dealer to get trans fluid? Anyone have any recommendations on where the fluid level should be when checking the fluid? I saw the above post from another member on how to go about checking the fluid above but was looking for any further detail. thanks everyone.

Low or very worn (dark) trans fluid won't allow the trans to shift correctly. If you find the fluid in either of these conditions have your trans serviced with a drain/fill using OE fluids only! If the fluid is dark you may need to have a drain/fill done twice, once now and they again when you get the next oil change. Flushing as they call it isn't recommended, even by Nissan!
Gary

will nissan trans fluid (used in auto 350z) be ok to use in the car? I will put a qt or two in this weekend to see if that takes care of the problem. If it does then i will perform a few drain and fills on the car. As i am not very familar with these cars (my first nissan/infiniti) would something as simple as low/burnt trans fluid cause the light to flash and the computer to send the vehicle as it seems into a limp mode??

Don't add trans fluid unless it's low, if it's dark just do a drain/fill very soon! Yes, the AT Z trans is the same used in our G35s.
Gary

ok, i will look into it this weekend and give an update.

Well.... Here's the update.. Fluid is good and at proper level. I was able to pull codes after driving it around the block. Codes are p1757 and p1759. I did some research and found the valve body in the trans is faulty. So it looks like I'll have to have that replaced or do a trans swap. In my 05cp is the tcm inside the trans? I'm considering just swapping out the trans...

I think the valve body is inside. There was a great DIY here written about installing a valva body upgrade. Maybe you can you look at that to help with your next decision? I think it's transgo valve.body you want to search for.

What part of PA you in? I live out in West Chester and have a Consult 3 tool same thing the dealer uses.

im in lancaster. So basically right down the turnpike from you ~50 miles. Im going to call the dealer today and get a price on the valve body. I can get a trans for $650 shipped with 60k miles on it and install it myself. So im trying to go the best route. I wonder what causes these valve bodies to go. And yes. It is inside the trans.