Chassis, generic

C0580 Brake Booster Motor A Phase U-V-W Circuit Low

Check engine lightOn
EmissionsNot relevant
Drive cycleNot required
Limp modePossible

C0580 flags a phase of booster motor A that is pulled too low, or a driver stage that cannot lift it properly. GM's 2016 and 2019 hybrid tables use it when the gate-drive supply of the bridge driver falls too far below the motor supply (7 V limit, 5 ms). In the 2019 IBC unit it covers a phase that does not drop under 0.99 V while its lower transistor conducts, a phase already near 0 V before the bridge is enabled, and an undercharged bootstrap capacitor – all Type A with MIL. Automotive gate drivers such as TI's DRV8305-Q1 report this charge-pump undervoltage themselves. Note the older meaning: on the 2011 Saab 9-5 and related GM cars, C0580 was the right front damper actuator of the adaptive suspension. In the booster meaning the module normally switches assist off.

Likely causes

Gate-driver or charge-pump supply in the brake module too low (internal defect or weak supply)
Phase lead of motor A chafed through and shorted to ground
Lower bridge transistor shorted or permanently driven

Symptoms

  • Electric brake assist off, pedal feels hard
  • Brake and stability warning lamps, on GM also the check engine lamp
  • Fault may appear right after switching the ignition on

Repair estimate

DifficultyHardWorkshop job
Parts and labour€150–2,800
Time1–4 h

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

Parts involved

brake booster motor amotor phase wiring

Related codes

C057FC0581C0582C0584C0591

References: gsi.ext.gm.com, gsi.ext.gm.com, gsi.ext.gm.com, ti.com.