OBD-II reference

All 9.533 generic OBD-II codes, explained in detail.

Causes, inspection steps and sources — a comprehensive DIY archive. Created and maintained with love for the detail. Good luck and have fun!

Powertrain generic / SAE

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.

SystemPowertrain
Typegeneric / SAE
GroupP0
Range / number7 / 86

Possible causes

  • Aged solenoid with weakened magnetic force high
  • Old, contaminated transmission fluid medium
  • Sensor element aged beyond calibration window low

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

Inspection / repair

  • Difficulty: hard
  • DIY: shop recommended
  • Estimated cost: 400–2500 €
  • Estimated time: 2–8 h
  • Component: shift timing solenoid a
  • Component: transmission fluid
  • MIL / check engine light

Sources

References

How to read OBD-II codes

The first letter names the vehicle system, the second digit distinguishes generic from manufacturer-specific, the remaining digits group fault area and number.

PPowertrain: engine, transmission, emissions
BBody: chassis trim, comfort, interior
CChassis: suspension, brakes, steering
UNetwork: CAN, control modules, communication