2015 Infiniti Q50

While operating the vehicle, the transmission suffered an abrupt failure resulting in Diagnostic Trouble Code (DTC) P0720 (Output Speed Sensor Circuit). Further diagnostic inspection revealed a complete internal failure of the integrated valve body assembly, which houses the Transmission Control Module (TCM), solenoids, and output speed sensors. The failure caused an immediate loss of gear selection, restricting the transmission to 3rd gear ("limp mode"). Attempting to accelerate beyond 3rd gear causes violent vehicle shaking, severe hesitation, and an inability to maintain traffic speeds due to the TCM losing signal input from the speed sensors and solenoid circuits. This total valve body/TCM failure creates a critical safety hazard. Sudden restriction to 3rd gear without warning on highways or during turn movements leaves the vehicle unable to match surrounding traffic speeds, creating an immediate risk of a rear-end or side-impact collision. The vehicle has been strictly maintained according to manufacturer schedules. Because Nissan/Infiniti designed the TCM and speed sensors as an integrated unit inside the hydraulic valve body, a sensor failure requires replacing the entire valve body/TCM unit—a repair quoted at over $3,000, with complete transmission replacement exceeding that cost. This valve body/TCM failure mode is widely documented among Infiniti Q50 owners sharing the RE7R01A 7-speed automatic transmission platform, indicating a widespread electronic and mechanical defect that threatens driver safety.

After starting the car the steering wheel jumps off center and the steering is all over the place. have to start the car again and the steering wheel jumps the other direction. I strongly suggest this is exactly what the June 13, 2016 NHTSA campaign number 16V43000 the software may reduce steering ability and increase risk of crash.the direct steering system my experience an error at vehicle start up altering the vehicle steering responsiveness and turning radius. Exact problem with this car. This car has been recalled for the driveshaft break NHSTA 24V470000

DIRECT ADAPTIVE STEERING EXPERIENCEING AT START UP ALTERING THE VEHICLES STEERING AND RESPONSIVENESS AND TURNING RADIUS DOES NOT WORK AND IS INCREASING THE RISK OF A CRASH. VERY UNSAFE TO DRIVE. THERE IS A RECALL 16V430000 ON THIS VERY PROBLEM. HAVE BEEN TOLD BY DEALERSHIP AND NISSAN MOTORS THAT MY CAR IS NOT ON THE RECALL AND I WILL HAVE TO PAY MY SELF TO GET FIXED AND TO SEE IF THAT IS THE PROBLEM. READING THE NHTSA CAMPAIGN NUMBER:16V430000 THIS IS THE EXACT PROBLEM WITH THE DIRECT ADAPTIVE STEERING SYSTEM ON THIS CAR. I BELIEVE THIS SHOULD BE COVERED BY THE RECALL!

While driving my 2015 Infiniti Q50s, the transmission suddenly suffered a catastrophic electronic failure, causing the vehicle to immediately drop into "limp mode." This resulted in a sudden and dangerous loss of acceleration while operating in traffic. A diagnostic scan revealed trouble codes P0500 and P0720 (Output Speed Sensor circuit). However, following Infiniti's official Technical Service Bulletin (TSB ITB19-040), the actual failure was the Transmission Control Module (TCM), which is permanently integrated into the transmission control valve body inside the transmission. Because the speed sensor cannot be replaced independently of the integrated module, I was forced to pay out-of-pocket to replace the entire transmission control valve body assembly and have a dealership program the new unit. This is a widely documented, premature failure on this vehicle platform that creates an immediate highway safety hazard when the vehicle drops power without warning.

DAS issue that I have been dealing with for two months now, issue is still not resolved even after taking out a personal loan for 6k to fix the modules at Douglas Infiniti, waited weeks for the modules, they replaced the modules, did the calibration but a new issue is happening where I'm losing control for a split second and the car would either pull to the left or right egregiously. I took it to back to Douglas Infiniti for the issue, they found code C13E9-00, cleared the code and did the calibration again only for the issue to happen again once I was close to getting home. Spoke with Martin the advisor and he is saying that he thinks its an issue with the rack and pinion and not a software issue. I bought the rack and pinion from infiniti's wholesale direct website, the rack and pinion came from Infiniti of Winston Salem, so it's an OEM rack and pinion, he said I should take it back to the shop where I got it installed and have them check their work, even though they were able to calibrate the system once the new modules were installed, certify their work and give me back to the keys to the car only for the issue to happen again. Took it back to DriveWorks Auto Center in Union, NJ and they couldn't find any issue with the rack & pinion, said I need a wheel alignment thought, went and got a wheel alignment. Driving home from work yesterday on [XXX] going down the hill and the car steering went out momentarily and the car started pulling to the right, straightened the wheel and now I was swaying to the right. I have a case open with Infiniti Consumer Affairs INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

The valve body on these cars are useless. Driving down a highway and cant shift out of 3rd gear almost had a car re-end me. Today I am driving and the ECU is not responding I see the check engine light on then I'm like not again. This would be the 3rd valve body I replaced. First I replaced the whole transmission thinking that is what I needed and advised that the valve body and the transmission are one. Yet no they come in parts. Anyways today I am waiting to get home, but the car is not reading my key fob why? Then the ECU and code U0100 is popping up. Something new and turns the car off. The shifting that happen earlier was just a light bulb of I already knew what is wrong. I felt the car shift with a hunch so I looked at my dash board and saw the check engine light again and was like not again. Please not again. Now on the dash board I see AWD and chassis issue. Then online I am told electrical problem and or ECU module not reading correctly. Like what is up with these push to starts. They are becoming a headache. I need to know just why I am replacing my valve body now for the 4th time???? This all can cause an accident that my car randomly slows down.

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.