Code result
P078D
Shift Timing Solenoid B High
High severity
What it means
Shift timing solenoid B control circuit reads stuck high — short to battery voltage or open coil.
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
Control wire shorted to battery voltage
highOne of the most commonly reported causes for this code — check this first.
Related help
Get the full diagnosis
Add your vehicle and see step-by-step repair help, recalls, and TSBs in Wrenchify.
Diagnose P078D freeNo credit card required