2005 G35 Sedan (AT) 58K

I'm relatively new to this forum but have spent quite a bit of time searching through it and I can't seem to find a thread involving these two specific codes...here's my issue:

Last week I stopped at an intersection and when I pushed the gas the car didn't move and the word "Slip" showed up under the D on my dash. Yesterday I stopped at a stop sign and when I pushed the gas the lights on my dash and shift console started flashing, the car was slow to engage & there was a grinding noise (sounded and felt like I was driving a MT and struggling to get it into gear).

I took the car to my local mechanic and he found codes P1815 and P1705. At which point he typed the codes into his computer program, said "this isn't good" and proceeded to tell me that the most common fix amongst his network of mechanics was a new transmission.

Long story short, I just bought the car and am hoping it doesn't need a transmission. Any info, advice and/or guidance from members who have had a similar issue and/or encountered these two codes simultaneously would be greatly appreciated!!!

 

So you purchased a thirteen year old vehicle with only 58k miles, never had the vehicle inspected by an Infiniti dealer prior to purchase to run the VIN number and provide you with a service history and now you are hoping for the best from a local non trained Infiniti mechanic?

Good luck

Telcoman

 

Telcoman...thank you for the thoughtful insight!!!

It gets worse though...the guy who owned the car before me only owned it for 5 months...and though I was skeptical I believed his story, ran a Carfax and bought the vehicle :/

sooo...youre right...I'm an idiot...cool...

Any chance we can move past the pompous forum posturing and discuss the codes, common issues, next steps and/or solutions?

 

I don't think that you are an idiot but you should have done more due diligence prior to the purchase.

Have you read the FSM on this vehicle?

http://www.nicoclub.com/FSM/G35/Seda...5_Sedan/at.pdf

See page AT-137 and AT-174

If the problems are in the harness keep in mind that there are hundreds of thousands of flood vehicles out on the market with washed titles.
The best advice I can give you is to have the vehicle thoroughly inspected by an Infiniti dealer. Have them run the VIN number. Was the vehicle originally purchased in your state or somewhere else that had major flooding?
Get an estimate of the needed repairs from the Infiniti dealer. You might be able to do the repairs yourself?
If you purchased a salvage vehicle and the seller committed fraud by not informing you you might have a recourse thru the legal system?

Good luck

Telcoman

 

P1815 is a problem with the man-u-matic mode however this might be related to the next code.

P1705 is the TPS throttle position sensor reading not being properly sent to the TCM which probably caused the harsh noises and such you heard. The transmission was expecting a certain throttle position so it picked a gear which lugged the motor substantially, then it realized something was wrong and threw the DTC and went into limp/stall mode.

I recommend towing the vehicle to Nissan for a diagnostic because they have the correct tool (Consult-II) to read actual data being sent between the ECU and TCM, they can read the actual TPS data to verify it's within range, if it IS within range and there isn't a damaged harness or other electrical problem like a ground then the damage occured inside the TCM which is basically the entire transmission, it's a very expensive part.

After Nissan tells you exactly what the problem is you can decide on how or WHO will perform the repairs, I wouldn't recommend a transmission replacement (or valve body/TCM replacement) by Nissan, that will be well over $1k and you're better off taking the vehicle to a specialty transmission shop for transmission repairs.

 

Update:

I took the car to Infiniti and the service consultant suggested I drive the car until the issue happens again. Which I believe he suggested because the original shop I took it to cleared the codes (in order to see which code shows up if/when the issue returns). I realize this was probably a bad idea but I always default to the experts (especially when I am out of my element).

So now I'm wondering:

1. Am I putting the car at risk (will the issues get worse and/or cause other more expensive issues) if I continue to drive it and wait for the problem to return?

2. The service consultant seemed to think that since the problem isn't occuring regularly, and the codes have been erased, that the tech/mechanic wouldn't be able to find the issue. Is this the case or should they be able to trouble shoot the situation based on my documentation of what happened and the codes that were present before being erased? Essentially, if I leave the car at the dealer and pay the diagnostic fee, should the mechanics/techs be able to successfully trouble shoot the issue(s)?

3. There seems to be a factory service bulletin for this issue:

https://www.google.com/amp/s/www.autocodes.com/amp/codes/p1705_infiniti.html

If the techs cant successful troubleshoot the issue(s) should I follow the FSB and replace the Transmission Valve Body...should I replace the Throttle Position Sensor...or should I do something different?

Any/all advice from those who have experience with this issue is greatly appreciappreciated!!!

 

^
Sell it before the trouble returns.
That is what the person did that you bought the vehicle from.

Telcoman

 

Telcoman, thank you again for your thoughtful response!

Would love to hear something constructive from someone who has experience with these codes/issues.

Thanks,

Jason

 

It's hard to say man, get the transmission serviced if it hasn't been done in the last 30k miles, it might be an intermittent lose wire inside the transmission, a bad ground causing the signal to be misread, perhaps intermittent failure of the throttle body.

Clean up the grounds to eliminate that as a possible problem, 2 on the top of the timing chain cover, one on the passenger side, one under the coolant reservoir, one on the chassis next to the battery as well as the negative battery terminal.

Eliminate the obvious and easy stuff and hopefully it never happens again.

 

+1 on what cleric said

 

Thank you Cleric!

Would you suggest taking the car to my local mechanic, Infiniti or a transmission shop for this type of service?

 

Your local mechanic should be able to follow the grounds, just make sure to inform him of all those ones I just listed, they need to be cleaned with a metal brush on the threads of the fastener, the crimped-on lug, and the mating surface for all the grounds. Apply electrical anti-oxidation grease and tighten them back down.

As long as your mechanic uses Matic-J or S transmission fluid in the tranny then he can perform that service as well, it's just a drain/fill of about 5 qt of fluid but it MUST be the correct type and not a generic.