P078A
Shift Timing Solenoid B
General fault on shift timing solenoid B — second timing solenoid for shift events that need a different ramp profile (typically downshifts vs. upshifts, or specific gear pairs).
General fault on shift timing solenoid B — second timing solenoid for shift events that need a different ramp profile (typically downshifts vs. upshifts, or specific gear pairs).
Common causes
- high
Solenoid electrical or hydraulic fault
One of the most commonly reported causes for this code — check this first.
Typical part cost: $440-2750
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First things to check
- 1Confirm the code with a scan tool and check for additional related codes.
- 2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.
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Related codes
See related trouble codes
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Frequently asked questions
What does P078A mean?
P078A means "Shift Timing Solenoid B". It is a generic OBD-II code that points to a fault in the transmission.
What are the most common causes of P078A?
solenoid electrical or hydraulic fault — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.
Can I keep driving with this code?
This code points to a problem that can cause damage or affect safety. Avoid driving and have the vehicle diagnosed promptly. Use the Wrenchify app for a full diagnosis specific to your vehicle.
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