C0596Brake Booster Motor A Current Sensor Circuit Range/Performance
- Generic OBD-II code · Chassis
- Turns on the check-engine light
- Can trigger limp mode
- How the car detects it
- C0596 questions the current measurement of booster motor A itself rather than the motor. GM's 2016/2019 hybrid booster tests its overcurrent comparator at start-up by forcing minimum and maximum PWM and reading the comparator output back over a feedback line, while the voltage behind the master switch must sit near zero or near battery voltage; a hardware overcurrent flag on that line during operation also sets it (30 ms). GM's 2019 IBC unit injects zero, positive, negative and common-mode offsets into the current sense path at power-up, with the motor almost still and 7.1–18 V supply, and compares the results with their allowed bands. All Type A with MIL. Driver chips such as TI's DRV8343-Q1 short the amplifier inputs on command for this zero calibration.
- What you may notice
- Brake assist warning right after switching on
- Heavy brake pedal, check engine lamp on
- Likely causes
- LikelyFaulty current sense amplifier or motor driver chip
- PossibleOvercurrent comparator or its feedback line not responding
- RareSupply voltage outside the test window during start-up
- Repair
- Workshop only · Usually a job for a workshop.Typical cost: €200 – €3,000
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.