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

P2030

Fuel Fired Heater Performance

The fuel-fired auxiliary heater is operating but not delivering the expected heat output within the calibrated time — flame sensor reports weak combustion, exhaust temperature does not rise, or coolant heating rate is below threshold.

SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number– / 30

Possible causes

  • Combustion chamber sooted from short cycles high
  • Flame sensor degraded medium

Inspection / repair

  • Difficulty: medium
  • DIY: shop recommended
  • Estimated cost: 120–900 €
  • Estimated time: 1–3.5 h
  • Component: fuel fired heater
  • Component: heater flame sensor
  • Component: heater combustion chamber

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