Network, generic

U0406 Invalid Data Received From Fuel Injector Control Module

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

U0406 means a receiving controller, normally the ECM/PCM, gets messages from the fuel injector control module that arrive but fail its checks: wrong counter, checksum, range or a signal marked invalid. Ford's 2012 OBD summary shows the U04xx principle with U0401: the TCM stores it when the ECM sends invalid or faulted torque or pedal data. A separate injector module exists only on some designs; GM's 2013 bi-fuel CNG Silverado/Sierra uses an FICM that switches the injectors and passes rail pressure and temperature to the ECM over serial data. No manufacturer documents U0406 publicly. As fuel delivery affects emissions, CARB requires such inputs to be monitored and a MIL is likely. U0105 means lost contact, U0306 a software mismatch.

Likely causes

Corroded or loose connector, damaged bus wire to the injector module
Low supply voltage at the injector module
Software levels of injector module and ECM do not match
Injector control module internally faulty

Symptoms

  • Check engine light on
  • Rough running, misfire or hard start
  • Reduced power

Repair estimate

DifficultyHardWorkshop job
Parts and labour€100–1,200
Time1–3 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

fuel injector control moduleengine control modulecan bus wiring

Related codes

U0105U0306U0401U0407

References: http:, static.nhtsa.gov, law.cornell.edu.