Code result
P078B
Shift Timing Solenoid B Range/Performance
High severity
What it means
Shift timing solenoid B is electrically intact, but actual shift timing does not match the model — same failure modes as solenoid A (aged, dirty ATF), applied to the second timing channel.
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
Aged solenoid with weakened force
highOne of the most commonly reported causes for this code — check this first.
Sensor element aged beyond calibration window
lowLess common, but worth ruling out after the more likely causes.
Sensor mounting loose - signal damping
lowLess common, but worth ruling out after the more likely causes.
Related help
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