P0786
Shift Timing Solenoid A Range/Performance
Shift timing solenoid A is electrically intact, but the actual shift time does not match the model — shifts too fast (harsh) or too slow (slipping under load). Often aged solenoid with weakened force or contaminated ATF restricting the regulating port.
- Check engine light: Yes
- Emissions related: No
- Repair difficulty: hard
Symptoms
- Check engine or transmission warning light on
- Harsh, delayed, or missing shifts
- Possible limp mode (locked in one gear)
- Slipping or shuddering during gear changes
Common causes
Ordered by how often each turns out to be the cause.
- Aged solenoid with weakened magnetic forceCommon
- Old, contaminated transmission fluidPossible
- Sensor element aged beyond calibration windowLess likely
Parts involved
- Shift Timing Solenoid A
- Transmission Fluid
P0786 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.