Network, generic

U02A7 Lost Communication With Engine Sound Control 1

Check engine lightUsually off

EmissionsNot relevant

Drive cycleNot required

Limp modeNo

Engine sound control means active sound design: a controller composes or amplifies engine sound from live data such as engine speed and torque and plays it through speakers or a structure-borne actuator, the way Volkswagen's Soundaktor or Kia's Active Sound System do. Where this runs in a separate unit, U02A7 records that unit 1 has stopped sending its network messages. Many makers integrate the function elsewhere: Ford's 2021 programme 21U04 for the Explorer ST and Lincoln Aviator had dealers activate active noise control and engine sound enhancement within the audio controller using the FDRS tool, because the plant had left them off. No manufacturer documents U02A7 publicly. Consequences are acoustic only: the synthetic sound is missing, the cabin may sound plainer.

Likely causes

Fuse, supply or ground of sound unit 1 faulty

Unit or function not enabled or wrongly configured

Bus wiring or connector to the unit damaged

Sound control unit 1 internally failed

Symptoms

Synthetic engine sound missing in the cabin
More audible drivetrain or road noise

Repair estimate

DifficultyMediumWorkshop job

Parts and labour€0–800

Time0.3–2 h

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

Parts involved

engine sound module 1vehicle bus wiring

Related codes

U02A8

References: en.wikipedia.org, static.nhtsa.gov.