Chassis, generic

C0583 Brake Booster Motor B Phase U-V-W Circuit/Open

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modePossible

C0583 refers to the second motor or second winding system, B, of an electric brake booster and reports an interrupted phase path there. Not every booster has a B side: GM's public tables diagnose motor A only, and no manufacturer documents C0583 in this meaning. GM's keyword list for 2014 and older vehicles (PIP5094) contains C0583 from an earlier numbering. A B channel makes sense in redundant layouts such as the dual-winding gear motor in a Hyundai Mobis patent, where two power modules each feed one three-phase winding and either one can carry the full current. An open B phase is found the same way as on side A, for example using the driver chip's open-load check. The module drops the faulty channel; depending on design, assist continues on A or is reduced.

Likely causes

Open winding or internal phase connection of motor/winding system B
Power module B with a transistor that no longer conducts
Loose or corroded phase contact on the B side

Symptoms

  • Brake warning lamp with a service message
  • Weaker or slower brake assist if only side A remains

Repair estimate

DifficultyHardWorkshop job
Parts and labour€200–2,800
Time1–4 h

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

Parts involved

brake booster motor bmotor phase wiring

Related codes

C0584C0585C0586C057FC0592

References: patents.google.com, ti.com, static.nhtsa.gov.