P0778
PowertrainTransmission Solenoidmoderate severityPressure Control Solenoid B Electrical
What P0778 Means
An electrical fault was detected in transmission pressure control solenoid B circuit. This can cause improper line pressure control.
Symptoms
- Erratic shifting
- Transmission slipping
- Check engine light on
Common Causes
- Faulty pressure control solenoid B
- Open or shorted wiring
- Poor connector contact
- Failed transmission control module
Diagnostic Steps
- Scan for related codes
- Inspect solenoid B wiring and connectors
- Measure solenoid resistance
- Replace solenoid or repair wiring
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