Skip to content
ediagtool.com WELCOME10 · 10% off orders $89+
U012D Network

U012D — Lost Communication With Generator A Control Module

Lost Communication With Generator A Control Module: the control module has detected this fault condition.

General code reference. Confirm the definition and diagnostic procedure for your vehicle's year, model and engine. A stored code alone does not identify a failed part.

Affected components

  • Generator a module
  • Can bus

Possible causes to check

These are possible checks, not a ranked diagnosis. Follow the vehicle manufacturer's test procedure before replacing parts.

  • Module unpowered
  • Gateway module routing CAN messages incorrectly
  • CAN terminating resistor (120 Ω) drifted out of spec

Possible 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

Diagnostic notes

  • The malfunction indicator lamp may illuminate
  • A drive cycle may be required after repair

Related codes

Sources

Check each reference's vehicle and model-year scope. General background links do not establish which fault is most likely on your vehicle.

Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.

You might like