C0593Brake Booster Motor B Phase U-V-W Current Low
- Generic OBD-II code · Chassis
- Can trigger limp mode
- How the car detects it
- C0593 is meant for a current value on booster side B that is too low or negative where the controller expects about zero or a commanded positive current. It is not documented by any manufacturer; like C0592 it shows up only in GM's old keyword list PIP5094 with a different meaning. Unlike the high fault, a low value rarely reflects real current: more often the measuring chain has an offset. TI's DRV8343-Q1 has a calibration input that shorts the amplifier inputs internally so the controller can store the zero point and subtract it, and a drifted zero leads exactly to such readings. GM's matching test for side A trips below −20 A or −38 A. In a dual-winding motor like the Hyundai Mobis design, module B is then shut down and module A carries the load alone.
- What you may notice
- Brake assist warning message
- Assist weaker under hard braking if only side A remains
- Likely causes
- PossibleZero point of the side B current measurement drifted
- PossibleDefective power module B or its driver chip
- RareHigh resistance in a side B phase connection
- 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.