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

P26EB

Alternative Fuel Control Module System Voltage

The alternative fuel control module reports a system voltage out of operating range. CNG, LPG, or hydrogen fuelling can be disabled until voltage is in spec.

SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number6 / EB

Possible causes

  • Weak battery sags voltage under load medium
  • Alternator output out of regulation medium

Inspection / repair

  • Difficulty: medium
  • DIY: shop recommended
  • Estimated cost: 120–1000 €
  • Estimated time: 0.8–3.5 h
  • Component: alt fuel control module
  • Component: charging system
  • 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