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

P26C6

Exhaust Flow Control Valve A Control Circuit Low

Voltage on the exhaust flow control valve A control line is below the expected window. The exhaust control valve modulates exhaust backpressure or routing (EGR feed, sound, regen support); a malfunction shifts torque mapping and may trigger limp mode.

SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number6 / C6

Possible causes

  • Control wire shorted to ground high
  • Internal short in solenoid coil medium
  • Connector pins corroded - high contact resistance low

Inspection / repair

  • Difficulty: medium
  • DIY: shop recommended
  • Estimated cost: 150–1200 €
  • Estimated time: 0.8–3.5 h
  • Component: exhaust flow valve a
  • Component: solenoid
  • Component: wiring harness
  • 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