P0780 Shift Malfunction

P0780 indicates a general shift malfunction. The transmission controller detected shift behavior that does not match the expected timing or ratio change.

Code details

Generic OBD-II · P0

System: Transmission
Code type: Generic (SAE / ISO controlled)
Standard: SAE J2012 / ISO 15031-6

Diagnostic boundary

A diagnostic trouble code reports that a monitored test failed. It does not prove one specific part is bad, and manufacturer logic can add vehicle-specific conditions.

Do not treat P0780 as a complete diagnosis; it is a broad shift fault that requires enhanced transmission data and companion codes.

Symptoms of P0780

Harsh, delayed, or slipping shifts, or being stuck in one gear.
Check-engine light, sometimes with limp-home mode.
Flaring RPM or a shudder under load.

Common causes of P0780

Low or degraded transmission fluid.
A failing speed sensor, shift solenoid, or pressure-control circuit.
Wiring, connector, or internal hydraulic/mechanical faults.

Useful checks before replacing parts

Review commanded gear, actual gear, input speed, output speed, shift timing, pressure data, and all companion transmission codes.
Check fluid level and condition where serviceable, plus range sensor, speed sensors, solenoid commands, and pressure-control behavior.
Identify whether the malfunction happens on one shift, multiple shifts, cold, hot, or under specific throttle load.

Related OBD-II codes

These nearby transmission entries can help compare wording and pin down the fault area.