P0786 Shift/Timing Solenoid Range/Performance

P0786 points to shift or timing solenoid range/performance. The solenoid circuit may work electrically but its response is outside the expected range.

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 diagnose this code from electrical resistance alone because range/performance faults can be hydraulic or mechanical.

Symptoms of P0786

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 P0786

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

Compare commanded shift timing, actual ratio change, solenoid command, input speed, output speed, and fluid temperature.
Inspect fluid condition, valve-body operation, solenoid resistance, harness integrity, and related pressure-control behavior.
Identify whether the symptom is delayed shift, flare, bind, harsh engagement, or no commanded response.

Related OBD-II codes

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