Code result
P078F
Transmission Mode Switch C Circuit
High severity
What it means
General electrical fault on the third transmission mode select switch input C — used for additional drive modes (Sport, Snow, Tow/Haul, Eco) on transmissions that offer more than two operator-selectable shift maps. Without a valid input the TCM falls back to the default mode.
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
Open or shorted switch wire
highOne of the most commonly reported causes for this code — check this first.
Related help
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