P0766: Shift Solenoid D Performance/Stuck Off
3 vehicles · 2 makes
Most Reported On
P0766 is an OBD-II diagnostic trouble code meaning “Shift Solenoid D Performance/Stuck Off.” This code means the Transmission/Powertrain Control Module detected that Shift Solenoid 'D' is performing poorly or appears stuck in the off position. Shift solenoids direct hydraulic fluid inside the transmission to engage the proper gears or apply the torque converter clutch, and the module monitors whether commanded shifts actually occur. P0766 sets when solenoid D isn't producing the expected result — the gear change tied to it doesn't happen correctly. This can cause harsh or missed shifts, slipping, or being stuck in a gear, sometimes triggering limp mode. This code is most commonly reported on 2011-2019 Ford Fiesta, 2021-2022 Ford Bronco Sport, and 2020-2023 Lincoln Aviator.
Common Causes
Diagnostic Tools
To diagnose P0766, you'll need an OBD-II scanner. Here are our recommendations at every price point.
ANCEL AD310 Classic OBD-II Scanner
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LAUNCH CRP123X OBD-II Scanner
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Vehicles Affected (3)
FAQ
What does P0766 mean?
P0766 stands for "Shift Solenoid D Performance/Stuck Off." This code means the Transmission/Powertrain Control Module detected that Shift Solenoid 'D' is performing poorly or appears stuck in the off position. Shift solenoids direct hydraulic fluid inside the transmission to engage the proper gears or apply the torque converter clutch, and the module monitors whether commanded shifts actually occur. P0766 sets when solenoid D isn't producing the expected result — the gear change tied to it doesn't happen correctly. This can cause harsh or missed shifts, slipping, or being stuck in a gear, sometimes triggering limp mode.
What are the most common causes of P0766?
The most common causes of P0766 are: Stuck or failed shift solenoid D, Low or contaminated transmission fluid, Clogged solenoid screen or valve body passage, Open, shorted, or corroded solenoid wiring/connector, Valve body wear or sticking spool valve, Internal hydraulic leak affecting the solenoid circuit, Faulty TCM/PCM solenoid driver. The specific cause varies by vehicle.
How much does it cost to fix P0766?
Repair costs vary widely depending on the root cause and vehicle.
Which vehicles are affected by P0766?
Au7o has documented P0766 across 3 vehicle models from 2 manufacturers: Ford, Lincoln.
Sources (5)
- NHTSAFord Fiesta PowerShift Transmission NHTSA Complaints
- TSB2021 Ford Bronco Sport TSBs (SSM 51011 hot slip, TSB 21-2268 P0766) - CarComplaints.com
- TSBSSM 51011 - 8F35 Transmission Slip On Acceleration From A Stop When Hot - NHTSA
- Forum2021 Bronco Sport Transmission Failure - Bronco Sport Forum
- TSBFord TSB 22-2428: 10R60/10R80/10R80 MHT Harsh or Delayed Engagement and Shift
Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.