OBD-II code · Network

U041D Invalid Data Received From Rocker Arm Control Module B

A receiving module detected implausible data from rocker arm actuator module B (variable valve lift / cylinder deactivation). Position or pressure feedback fails plausibility checks and is rejected.

Is it safe to drive with U041D?

The car may go into limp mode (reduced power). Get it diagnosed before a long trip.

Common causes

  • Most likelyModule internal fault or sensor input drift
  • PossibleSoftware version mismatch after replacement
  • Less likelyGateway module routing CAN messages incorrectly

Symptoms

  • Multiple warning lights may illuminate
  • Affected modules may go into limp mode or shut down
  • Specific functions inoperative depending on module
  • Diagnostic tools may show communication faults

Repair at a glance

Difficulty
Hard
DIY friendly
Best left to a mechanic
Typical labour
1–5 h
Emissions test
Likely to fail
After the fix
A drive cycle is needed before the light stays off
Parts involved
Rocker Arm Module B

Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.