The P0762 code in your 2023 Infiniti Q50 indicates shift solenoid C is stuck in the engaged (on) position within the 7-speed automatic transmission. This condition causes the solenoid's controlled clutch pack to remain engaged when it should release.
Q50 Transmission Architecture
The Infiniti Q50 uses a Nissan/JATCO 7-speed automatic known for smooth, responsive shifting. Shift solenoid C controls specific gear engagement sequences. When stuck on, the transmission cannot properly release that clutch pack for normal gear progression.
What Causes Solenoid C Stuck On
- Internal solenoid mechanical failure
- Electrical short holding solenoid energized
- Valve body debris preventing return
- Contamination in solenoid valve
- TCM continuously commanding solenoid
- Mechatronic internal fault
Symptoms of P0762
- Gear ratio conflicts
- Transmission stuck in gear
- Severe shift quality issues
- Check engine light
- Possible no-drive condition
- Limp mode activation
Infiniti Service Considerations
JATCO transmissions often require Nissan/Infiniti Consult diagnostic equipment for full access. The Q50's transmission is shared with several Nissan platforms, so TSBs from either brand may be relevant.