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

P0A12

DC/DC Converter Communication

The hybrid control module loses CAN bus communication with the DC/DC converter for longer than the fault threshold.

SystemPowertrain
Typegeneric / SAE
GroupP0
Range / numberA / 12

Possible causes

  • CAN bus fault high
  • Converter unpowered or offline medium
  • Gateway module routing CAN messages incorrectly low

Inspection / repair

  • Difficulty: shop only
  • DIY: shop recommended
  • Estimated cost: 400–3000 €
  • Estimated time: 2–8 h
  • Component: dc dc converter
  • Component: can bus
  • Component: hybrid control module
  • 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