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U027B

Lost Communication With Battery Charger Control Module D

The vehicle bus reports loss of communication with battery charger control module D. AC/DC charging coordination for the high-voltage battery via this node is suspended.

  • Check engine light: Yes
  • Emissions related: No
  • Repair difficulty: hard

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

Common causes

Ordered by how often each turns out to be the cause.

  • Bus wiring open or shortedCommon
  • Module without power or groundPossible
  • Module failedPossible

Parts involved

  • Battery Charger Module D
  • Vehicle Bus Wiring

U027B is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.