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

P20D7

Exhaust Aftertreatment Fuel Supply Control Circuit/Open

The control circuit for the dedicated aftertreatment fuel supply pump or solenoid is open — HC dosing into the exhaust will fail.

SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number– / D7

Possible causes

  • Winding or coil open high
  • Pin pushed back out of connector body low
  • Cracked solder joint inside the module or sensor low

Inspection / repair

  • Difficulty: hard
  • DIY: shop recommended
  • Estimated cost: 150–1200 €
  • Estimated time: 0.7–3.5 h
  • Component: aftertreatment fuel pump
  • Component: aftertreatment fuel supply solenoid
  • MIL / check engine light
  • emissions-relevant

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