C05A6ABS Pump Motor Supply Voltage B Circuit High
- Generic OBD-II code · Chassis
- Can trigger limp mode
- How the car detects it
- C05A6 says the second pump motor feed, supply B, carries more voltage than allowed. Overvoltage strains the motor and above all the transistors that switch it; gate driver ICs for brake motors such as TI's DRV8305-Q1 therefore watch their supply and raise an overvoltage warning in the mid-30 V range. Typical causes are a faulty alternator or DC/DC converter regulator, jump-starting or charging at too high a voltage, or a measuring fault in the module. No maker documents C05A6 publicly. As an orientation, Mitsubishi's 2023 Outlander PHEV specifies 10–16 V for the motor feed and stores C1056-17 once the brake unit's supply reaches 16 V within 1 s. Where the motor has two power modules on separate inputs, as in a Hyundai Mobis patent, the faulty side can be disabled while the other keeps working.
- What you may notice
- ABS/ESC warning lamp on, possibly with other overvoltage codes
- Very bright lights or battery warning if charging is the cause
- Likely causes
- LikelyAlternator or DC/DC converter regulating too high
- PossibleJump start or battery charger with excessive voltage
- RareVoltage measurement fault in the brake module
- Repair
- Medium · Often possible to do yourself.Typical cost: €0 – €900
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.