2015 Infiniti Q50

The transmission speed sensor has failed needs a new valve body. It seems like a very common problem with this car and it’s a $3000 fix according to my mechanic. I think there needs to be a recall issued considering everybody on this website is reporting the same problems.

Transmission Control Body. Lost of speed during driving which put me in danger of being hit from behind on the highway. The car was scanned and came up the code P0500 and P0720.

The door lock of the driver's door is stuck in the locked position and the door cannot be unlocked or opened. It will not unlock using the key fob, nor with the manual control inside the door, nor with the emergency key from outside the car. This could trap an inured driver inside the car in the event of an accident. The car has not yet been inspected by anyone. There was no warning lamps or messages prior to the failure. Earlier that same day the door failed to open while in gear but did so when I shifted to park. As this car was very recently purchased by me and I am still learning about it, I failed to recognize this a symptom of an impending failure. Regardless of that warning, total failure occurred the same day. As a graduate engineer who has worked in engineering related fields for more then 50 years I can recognize that a failure mode such as this is both a health and safety hazard to occupants in the event of an accident and a design defect that should not be allowed to be sold to the general public. Thank you for any consideration you give this complaint.

Unknown. Started to make left turn steering made loud banging noise then lost all power. Stepped on gas pedal would not go lost steering control and coasted to a stop. Adaptive steering went out. Almost got hit by on coming traffic.

Was making a left turn when the steering stopped working and the motor lost power, the adaptive steering quit working after approximately 15 mins. I started the car and it was working. Went a half mile made a right turn and it went out again. Shut off the motor tried to start it and could not. 20 mins later it started and has been working since. Dealer couldn't find the problem and wouldn't fix it, they also said that their were no recalls but I know that is not true. Infiniti had a law suit brought against them for the adaptive steering issue. If they fixed it why doesn't it work right.

The car just slowed down super fast on freeway almost got rear ended. It would not go past 3rd gear. Poor acceleration. Could have caused a huge accident. I got it diagnosed and they said it is valve body/speed sensor/tcm and they said this is a COMMON problem for 2015 Q50. I replaced this part 2 years ago and here we go again. Shop diagnosed and said this tcm (transmission control module which is in the transmission) but they have to change whole transmission. Everything happened all the sudden then check engine light came on.

Transmission valve body failed while driving which caused shifts to be limited. It could have caused an inability to shift at all, which is a safety issue. This issue has been inspected and confirmed by an independent shop. No warning signs were present before the failure. Furthermore, this issue is well known to Infiniti. It’s caused by breakdown of the transmission fluid overtime, causing a reduction in the cooling capacity of the fluid. But Infiniti says that the fluid should be lifetime. This overheating causes the TCM on the valve body to fail. If it failed while I was going at a highway speed I could have been injured.

Adaptive steering clicks and looses control. Steering wheel jerks back when self aligning. There was a recall for this I believe in June 2016. For 2015 infinity Q50’s but my VIN says that it wasn’t recalled but is the exact description of what is happening.

The contact owns a 2015 Infiniti Q50. The contact stated while driving 40 MPH, the accelerator was depressed; however, the vehicle failed to shift into gear properly, with the check engine warning light illuminated. The vehicle was able to be restarted. The vehicle was taken to an independent mechanic, where it was diagnosed that the transmission valve body had failed, and the transmission needed to be replaced. The vehicle was not repaired. The dealer was not contacted. The vehicle was not diagnosed or repaired. The manufacturer was made aware of the failure. The approximate failure mileage was 94,150.

Just over 1 week ago, I was leaving a parking lot and driving back to my home when my car wouldn't accelerate past about ~10-15 miles per hour and wasn't shifting gears. When I took my foot off the gas pedal, the gear just dropped immediately from above third to first gear and the car shook. I first noticed this when already out of the parking lot and pulling off from a median onto the road, with no engine light or other warnings. I quickly pulled into the turn lane where there wasn't traffic and turned the car off and back on. It was the same but luckily I was in eyes view of my apartment, so I drove under 10 mph and made it home. I took the vehicle to a transmission service center and the error code that came up on the computer was (P0500 - Vehicle Speed Sensor A), which the service center said is an issue with the "valve body" inside the transmission, specifically the "TCM - Transmission Control Module" that sits on top of the valve body. I contacted multiple Infiniti service centers and they all confirmed that the valve body for my vehicle (part# 31705-x133a) is back ordered by over a month and could be longer until they have it. They do not sell the Transmission Control Module separately. The valve body was quoted to me for $2200 for the part alone. I attempted to install an aftermarket valve body and a new error code came up on the computer (PO720 - Output Speed Sensor Circuit). I kept the original valve body and will hold onto it. Doing some more research, this appears to be a common issue with the Infiniti Q50 - [XXX] In addition to the reddit thread above, a quick google search for Infiniti Error codes P0500 and PO720 point to multiple sources indicating the same common experience and outcome. My vehicle has 110k miles and users in the reddit comments are also reporting the same issue with the TCM Transmission Control Module occurring between 85k - 100k miles in all cases. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Transmission intermittently will not shift to the next gear. Sometimes will not shift from first gear, other times will not shift from 3rd gear. Sometimes no issue at all. It is intermittent and no warning to when the issue might happened. It happens when trying to accelerate and has put me in an unsafe situation trying to accelerate on the highway or around town.

i’m reporting issues with the valve body on a 2015 Q50. I have had to replace the valve body already at cost of $1700. Many others have had same issue as this is a common defect with the TMC part. This needs to be addressed as a recall.

Air bag light suddenly said “passenger airbag off”. Don’t have to brake to switch gears. Steering at times feels a bit off.

Transmission, Transmission Valve body, speed sensors. After transmission shifting issues while traveling the interstate I had to have the car towed to the dealership. After the multi point inspection was performed serveral recommended itmes related to the ongoing performance and SAFETY of the vehicle listed below: Transmission $10,446.65 Transmission Valve Body $3693.92 The diagnostic code P0720. Attached is the service bulleting stating they know this will happen and when it does here's how to fix it. Yet they have never recalled the defective transmission. When I contact Infiniti consumer affairs they simply say that they cannot help me because the vehicle does not have warranty. If i had warranty then I would not be reaching out to them for assistance in replacing the transmission.

Transmission failure without warning!!

While driving on the interstate and coming over an overpass there was unavoidable debris located in the road. Immediately after passing over the debris there was a loud noise followed by jerking and the RPM's revved up almost like the car was in neutral. I let up off of the accelerator and then tried to accelerate again. The car would not go faster than 30mph and will not shift out of 3rd gear. I had the car towed to the dealership and the diagnostic codes reflected vehicle speed sensor and there was no physical damage that was visible under the car. I was told that the problem was in the transmission and that it would need to be changed and given an estimate that totaled over $10,000. I was also told by the service advisor that this is a known issue with the Infiniti Q50. After doing researching this a common problem and the consumer is having to pay out of pocket if the warranty has ended. This incident could have ended badly while doing 70mph on the interstate and the car just quits moving. With all of the complaints that I have read over in regards to the transmission issues yet no action has been taken to investigate this problem. It is obliviously a manufacturing issue and the consumer should not have to pay out of pocket for defective transmissions. This luxury car was not a cheap purchase. Very disappointed that with so many cases an investigation has never been done. Infiniti should be held accountable and a recall should be issued for this problem. I will not stop until I can get through to someone that can help.

P07200 code came up, transmission is no good because of a cheap sensor that's impossible to fix. seems to be very common and very inconvenient

Sitting in parking lot when a malfunction warning popped up with the dashboard lit up. Steering wheel, traction control, front and rear collision control and chassis system control system error. Had car towed to the dealership to find out it was DAST Steering control units. EPS/DAST 3 DTC C13D5-00 Control module, Chassis Control DTC C1B90-00 DAST System, DAST 1 DTC C13E9-00 Booting Angle Processing, DAST 1 DTC C13EB-00 Booting Angle Processing, DAST 2 DTC C13EB-00 Booting Angle Processing.

Upon driving when purchased the Engine Light for the Air Bags illuminated. Upon researching the issue the problem seems to be a common problem for vehicles of this make and problem. 90% of the time requiring the owner to take the vehicle to the dealership.Since it is a trend and ongoing I wanted to report the issue.

I received a recall notice (folded information card) from Infinity in the mail in about August 2024 regarding Recall NHTSA 24V-470-R24A7. I also received an email from Infinity on August 28, 2024 with Subject "Your Q50 is due for Important recall repairs " and noted it stated Recall Code R24A7/R24A5: NHTSA 24V-470: Recall Description Q50/Q70 Prop Shaft. I contacted Infinity to schedule the repair and received a confirmed email service appointment for October 4th 2024. When I arrived at the dealership the service department told me they did not have parts but would change my oil and do other service for a fee. All I wanted was the recall fixed. In total I've been to the dealer 3 times and been always told that they have not received parts from the manufacturer. Today I called Infinity Consumer Affairs Department at 1-800-662-6200 and spoke to "Dennis". He did little but talk in circles and did nothing to provide information and when the recall would be fixed. Since I was getting no information and he was not listening or helping I told him I was ending the call and calling the NHTSA, which I did and spoke with Tyronda. Confirmation number for call she gave me is [XXX] for our call. After my repeated efforts and complaints, Infinity appears to have no interest on fixing the vehicle recall they first advised me of in August, only seemingly "going through the motions" as slow as possible. My car is not fixed after about 4 months and they have done nothing to contact me as to when it will be repaired. That is my complaint INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)