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

P201B

Intake Manifold Runner Control Actuator Supply Voltage Low (Bank 1)

The supply voltage feeding the IMRC actuator on bank 1 is below the lower limit — typically a fuse, relay, or harness fault on the supply rail.

SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number– / 1B

Possible causes

  • Supply fuse blown high
  • Open supply wire medium
  • Supply relay contacts pitted medium

Inspection / repair

  • Difficulty: medium
  • DIY: possible
  • Estimated cost: 20–250 €
  • Estimated time: 0.3–1.5 h
  • Component: imrc actuator
  • Component: imrc supply relay
  • Component: imrc supply fuse
  • 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