NHTSA Owner Complaint Log
This page lists owner-reported complaints filed with NHTSA for the 2015 Infiniti Q50. Complaints are unverified consumer reports submitted to NHTSA and do not by themselves prove a defect or defect rate.
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)
The valve body went bad at 164k miles. Im not the only one. On all the forums and fb groups im on, there are hundreds of valv bodys going bad on the q50s for this general area of the year. On my facebook group i have seen 4 people in the past 2 days with theirs going out. Code p0720. Mine is being hauled to the shop right now so i dont have paperwork of replacement at this time for a few days
Valve body on my car and friends have gone bad, it’s a known issue within the Infiniti vq37 community
The contact owns a 2015 Infiniti Q50. The contact stated that while driving at an undisclosed speed, the vehicle stalled. The contact was able to drive the vehicle off the highway and park the vehicle. The contact stated that the failure occurred while the contact was driving on a busy highway. The vehicle was towed to the dealer where it was diagnosed with transmission valve body failure. The contact was informed that the transmission valve body needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure and a case was filed. The failure mileage was approximately 74,000.
The valve body/TCM shorts out on the car unexpectedly and can happen at any time causing the car to be unable to go past third gear. This is an known problem with 2014-17 Infiniti Q50 & there is a service bulletin issued by Infiniti associated with this problem published in November 2019. This vehicle was inspected by Infiniti dealership and they confirmed the issue. There was no warning light or prior to this event. After the failure this codes popped up P0720. Repair was ~$3500
My engine light came on at 115,946 miles causing my vehicle not to accelerate or shift properly which could have resulted in a accident. The vehicle was diagnosed at local Nissan dealership with code P0720 and P0500 stating vehicle need a transmission. Prior to this diagnose this vehicle was diagnose twice by a Nissan and Infiniti dealership concerning the shifting and acceleration issues but could not duplicate the issue at the time. I see where numerous car buyers are stating they’re having the same issues with the Infiniti brand at low miles and high miles.
P0500 vehicle speed sen/cir P0720 a/t veh speed sen/ circuit-or- output speed sensor P1574 ascd vhcl apps sensor - or lcc vhl spd sen (icc models) My safety was put at risk when the vehicle hesitated and stop changing gears while traffic was behind me. The vehicle was inspected by a local dealership which was Nissan and also Infiniti including a transmission shop named ammco. There were no warning lights that would indicate the vehicle was failing until April the 5th
the miles on the car were changed and trying to sell without the information aswell as the car is trying to get sold as a salvage title car without dealer license on facebook but they tempered with the miles on the car making it look like it only has 30k when in reality it was last reported to have 180k
Car pulled to the left unexpectedly and constantly for like 5 mins staright then it corrected it self.
Power steering failed while driving in parking lot looking for parking spot. Unable to turn wheel without hitting parked car. I was able to drive to end of the lot where there were less cars. Noticed that I was able to turn wheel so long as didn’t step on brakes. The steering wheel was also off alignment. This happed on a Saturday evening, next day car was fine all the warning were off. Spoke to service person explained what happened. He basically said if the car is running fine they can check it out but may not find the problem. Since the car was running fine until it wasn’t. Car was parked in garage turned on the car all warning lights go on. Made appointment for 4/3/24 drove car to dealership which is not to far. The warning lights still on and no power steering. Analysis many DTC codes found related to this system:B2512 4WAS SIG: C1B9000 DAST SYSTEM: C1138 4WAS CIRCUIT & C1A04 ABS/TCS/VDC CIRC. Correction Recommended to perform DAST calibration first before performing further diagnosis. COST $539.15 . They also did Multi-Point Inspection items requiring immediate attention Engine Air Filter COST $94.99 GRAND TOTAL $641.64 out of pocket. 4/3/24 picked up car. On that evening drove the car and as I’m pulling up on drive way power steering goes out again. I managed to get the car in garage. Once I’m in push button to close garage doesn’t work and car dies no power at all. Able to get car started by playing with battery cables. On dealership notes car was there 30 miles ago. Now they say wrong battery size. That battery was replaced by them on 2/28/22. Also the battery just past Multi-Point 2 days ago.New battery cost $232.78 now out of pocket $874.42.This is now 4/10/24. Drove that evening and front splash guard fall off had to tie wrap to hold whatever pieces are left. Took it to dealership they took no responsibility. I will need to replace it. I have all my receipts from them they are the only ones who have worked on my vehicle.
Car starts up and a little like the battery is having issues with loss of power. The dash board then shows multiple warning lights such as a batter, steering, and stability control. I turn the car back off and then back on and the steering light stayed on. The steering wheel is stuck but the car still moves forward and backwards with very stiff steering. In the past I had the issue checked by getting the steering wheel fluid exchanged and had multiple alignments since . The car would show signs of stiff steering when parking it will get wonky and like won’t move and bumping into a curb with the rear wheels will trigger it every once in a while. The steering has been an ongoing issue for the last year and I can’t figure out what it is but I did find out by Google searching that there was a recall on other models like mine with powering steering assist .
My car started acting weird, fob wasn’t working correctly, doors repeatedly lock nonstop and drained battery. I took to Infiniti and they said it’s water damage from my sunroof drains. It damaged my BCM. Infiniti has quoted me 3,700 dollars to fix. I’ve done lots of research and this seems to be a very common problem with the Infiniti q50 models. I believe this is a manufactured defect. This could of left me stranded because car wouldn’t crank.
My braking system completely failed while I was driving with no warning of sound or dash safety indicators. The only way I was able to stop my vehicle is by shifting into park while I was in motion. Two days prior to my car losing all ability to brake, my car was routinely serviced by the local dealership. All check points were green, including my brakes. The dealership towed my car back to the service center to inspect. The diagnostics came back as the break actuator unit (computer sensor) shorted which led to no communication to the brake control assist unit (computer sensor). This loss of communication between these sensors basically caused my brake functions to fail. I was fortunate to have been leaving a parking garage and not on the open road. This could have been a fatal incident. The repairs are $7000 of which Infiniti has only offered to cover $3000. This is a safety issue and a loss of faith with Infiniti as a vehicle manufacturer. There needs to be an investigation so no lives are lost. My vehicle is still not fixed.
The contact owns a 2015 Infiniti Q50. While driving at various speeds, the transmission was slow to shift. The vehicle failed to properly accelerate while depressing the accelerator pedal, and the check engine warning light remained illuminated. The vehicle was taken to a local transmission mechanic to be diagnosed, and it was determined that the gear ratio and speed sensor inside the transmission valve body were faulty, and that the valve body needed to be replaced. The valve body was replaced, and the failure was repaired; however, one week later, the failure reoccurred. The vehicle was taken back to the mechanic, and it was informed that the transmission needed to be replaced. The vehicle was not yet repaired. The manufacturer and local dealer were not contacted. The failure mileage was 99,000.
My car would not accelerate over 40 mph randomly after work. Once i noticed and tried to shift to a lower gear the car did not shift gears at all. When these things first happened there was no indicator lights on. The next morning the check engine light came on and the code pulled was P0720. After finding a repair shop to look further into the issue I was advised the car needed a new transmission to fix the issue. $4,000+ for the repair and as i google the issue I see that this is a common issue and it seems to always happen unexpectedly side note: also should be a recall on driver side blend door.. i almost died this summer due to cold air only blowing on one side in the middle of summer in 100• degree weather.
Sun roof drain is clogged which has caused my carpets to go wet literally puddles, could potentially damage my electronics in car this is an ongoing problem for thousands of Infinitis. I am in a group on Facebook and I can literally scroll and find hundreds of Infiniti owners complaining about their carpets and how Infiniti dealerships charging thousands of dollars to repair. I’ve been holding off to get this fixed in hopes that I’d find someone to assist me with a lower price but nothing
$2000+ to fix but not recalled for Yet Way too more than thousand Infiniti Owners has had the same issue with Valve Body Code:P0720
I was in a car accident during the summer, I was driving at speed limit when I came out the curve the car started sliding, and I went off the road and roll over at 4 times and ended up in a ditch upside in some water, but NO AIRBAGS went off I have pictures showing so, I try to tell the dealer I bought it from Car Max and even my insurance but no one seem to care but now I found this page. I also had a police on site and no ticket was issued to me since no proof of me driving recklessly I did have a police report but I can’t find it since it was back in the summer
The contact owned a 2015 Infiniti Q50. The contact stated that while driving approximately 5 to 10 mph, she experienced a diabetic medical emergency. The driver was unable to feel her legs or feet to stop the vehicle and crashed into the rear of an unknown SUV. The air bags did not deploy. The air bag warning light illuminated at impact. A police report was filed. The driver was taken to the emergency room by ambulance. The fire department was on the scene, but there was no reported fire. The vehicle was towed to a tow lot. The vehicle was later towed to a collision center. The contact called the local dealer, but the vehicle was not diagnosed or repaired. The vehicle was deemed a total loss by the insurance company. The manufacturer was contacted, but no assistance was provided. The failure mileage was approximately 50,000.
The speed sensor on car seems to have failed unexpectedly while driving over a bridge. The car would barely move and could have become a dangerous situation for multiple people had it been typical traffic. The issue seems to be that although the sensors are corrupted, the entire valve body or transmission must be replaced to solve the issue leaving the car inoperable. The car is currently at a repair shop. The engine light did come on shortly after. PLEASE ISSUE RECALL. https://static.nhtsa.gov/odi/tsbs/2019/MC-10168892-0001.pdf
The contact owns a 2015 Infiniti Q50. The contact stated that while driving at highway speeds, the vehicle inadvertently slowed down. The vehicle failed to accelerate. The check engine warning light was illuminated. The vehicle was towed to the local dealer where it was diagnosed that a valve body replacement was needed. The vehicle was not repaired. The manufacturer was contacted, and the contact was informed that the vehicle was not covered under warranty. The failure mileage was approximately 56,000.
4/16/2023 Sunday 5pm With my wife and daughter in the car, I started the vehicle in my driveway and selected Sport mode as usual. Selected reverse and backed into our turnaround then forward to the end of our driveway. Driveway is approximately 4 car lengths long with a 20 ft long apron turnaround. Almost immediately after braking at the end of the driveway while waiting for passing traffic to exit drive, vehicle suddenly accelerated and I immediately pressed the brake as hard as I could to prevent driving into passing vehicles. I could hear the tires trying to grip/spin while I was fighting to press the brake harder to hold it t back. I then panicked and selected the gear shifter to anything other than drive and it immediately did the same in reverse. After getting in into park, I immediately selected Standard mode and the vehicle performed normal afterwards. There were no warning lights or anything to indicate any issues. Previously I had noticed minor intermittent issues of high RPMs when slowing or braking while in Sport mode but it would immediately correct itself. I have not had a chance to take it for inspection as it's now Monday morning April 17. We were all very shaken. Please advise.
I was driving perfectly fine and i stopped at a red-light. I went to accelerate and the car wouldn't shift out of first gear and then check engine light came on. I pulled over and scanned the codes, it showed code p0500. After bringing to shop and reading thousands of different things from people who own the car online all said the same thing. Transmission valve body is shot. I almost got rear ended when i let off the gas because the engines rpms were so high casuing quick engine braking.
Transmission valve body failed and is a common problem for 2014-2016 I was on a busy road and the car threw check engine light and wouldn’t accelerate any more. I risked my safety and others because I was stopped in the middle of the road and lots of commuters passing by and the vehicle was fully registered and inspected by the state prior that happened but it’s a common problem that you’ll never know when it will fail.
The contact owns a 2015 Infiniti Q50. The contact stated that while driving approximately 50 MPH, the vehicle began to overheat and smoke was present coming from under the hood. After stopping to inspect the vehicle the contact opened the hood and flames were present in the engine compartment. The contact immediately extinguished the flames using water. The vehicle was later towed to the local dealer. The cause of the failure was not yet determined. The contact indicated that prior to the fire the vehicle had also experienced transmission shifting failures and the front driver's side and passenger side seat belts were locked in the retracted position and could not be used. The cause of the failures was not determined. The manufacturer was not notified of the failures. The failure mileage was 80,000.
The car was being driven on a normal day and while in gear and driven the car stalled and would no longer shift automatic. The car will not come out of 3rd gear. Took the car to repair shop and was told is a known issue with this model and even the transmission or transmission valve body needs replacement. Infinite will not issue recall and I have reach out to corporate on the issue the repair want 8,000 to replace transmission the car is out of extended warranty that was purchase on the vehicle I’m only the second owner of the car well maintained and should not be having this issue of a self maintained transmission with a vehicle worth 25,000 wen brought.
My car has 60,000 miles on it and multiple mechanics as well as the Infiniti dealership tell me it needs a new transmission. $8,000. It will not shift above 2nd gear. I took the valve body and manifold out of the transmission and was surprised to find that the output speed sensor plug is actually a dumby plug that connects to nothing. I've had cars with hundreds of thousands of miles on them still driving with the same transmission they were born with. I've rebuilt a lot of engines, but never had to replace a transmission, especially not after 60,000 miles. Any, I searched the internet and noticed that it's a very common problem with this vehicle.
I was driving and tried to turn but had lost complete control of the steering and hit the curb infront. Luckily i was only going 5-10 MPH so the impact was not terrible. My biggest concern is a lot of times my mother drives that car who is permanently disabled in one hand so I can only fear what might happen if she was the one driving the car.
The valve body/TCM. Yes the vehicle is available for inspection. The valve body/TCM shorts out on the car unexpectedly and can happen at any time causing the car to be unable to go pass third gear. This can occur on the freeway, or when trying to avoid an accident. This is an known problem with Infiniti’s & there is also an service bulletin associated with this problem. This vehicle has be inspected by the dealership and they confirmed the issue. There are no warning light or and thing prior to this event. After the failure this codes popped up P0720 & P0500. This occurred on Aug 13, 2022
Valve body went out with 89k miles and had to get transmission replaced.
Brake Pedal sinks to floor slowly at Red Lights. Randomly vehicle will yank seat belt back when abs module detects no brake fluid pressure once in a blue moon. This is because of the defective ABS module hydraulics leak internally from the factory. As brake fluid heats up the internal leak gets worse. Most likely check ball to pump or out valve leaking by. Model year 2015 for sure. I never got it covered under warranty because the problem starts out very random and takes a lot of time for it to always happen. Dealers will just say no problem found. ABS module cost $1k for me to buy at the dealer. Now I have brakes all the time again no thanks to a factory defect module randomly giving poor to no braking power. Internet forums of 2014-2016 have many people saying the same thing. Not the master cylinder, it is an internally leaking ABS module and will have no codes. Not happy about paying to replace a factory defective part.
Data synced from NHTSA on May 4, 2026