P0777
PowertrainTransmission Solenoidmoderate severityPressure Control Solenoid B Stuck On
What P0777 Means
The transmission pressure control solenoid B is stuck in the on position. This leads to excessive line pressure and shifting problems.
Symptoms
- Harsh shifts
- Transmission overheating
- Delayed engagement
Common Causes
- Stuck pressure control solenoid B
- Contaminated transmission fluid
- Faulty valve body
- Wiring or connector fault
Diagnostic Steps
- Check fluid level and condition
- Scan for stored codes
- Test solenoid B for stuck operation
- Inspect valve body and replace solenoid if faulty
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Budget handheld~$40
ANCEL AD410 →
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Serious DIY~$100
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Autel MaxiCOM MK808S →
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✓ Autel official store
Pro diagnostics$1,500+
Autel MaxiSys MS906 Pro →
Full-system pro platform — topology mapping, ECU coding, the works.
✓ Autel official store
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