Code result
P0777
Pressure Control Solenoid B Stuck On
High severity
What it means
Pressure control solenoid B does not release line pressure when commanded — output pressure remains at maximum, leading to harsh shifts and elevated stress on the clutch packs and seals.
Is it safe to drive?
No — stop driving
This code points to a problem that can cause damage or affect safety. Avoid driving and have the vehicle diagnosed promptly.
Most likely causes
Solenoid stuck open by debris
highOne of the most commonly reported causes for this code — check this first.
Contaminated ATF clogging the pressure control valve
mediumA plausible cause — test and verify before replacing parts.
Carbon or debris buildup preventing free movement
lowLess common, but worth ruling out after the more likely causes.
Related help
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