C0542Brake Pressure Sensor B Circuit Low
- Generic OBD-II code · Chassis
- Turns on the check-engine light
- Can trigger limp mode
- How the car detects it
- Brake pressure sensor B pulls its signal below the lowest voltage the receiving module treats as valid. Two makers name the code in public bulletins. Bentley lists C054200 in the ESC unit J104 of the Continental GT/GTC and Flying Spur alongside C054100, with adaptive cruise switched off and the J104 replaced. Stellantis lists C0542 as Brake Pressure Sensor 2 Circuit Low among powertrain-module faults of the 2019 Jeep Cherokee with 3.2-litre V6 and engine stop-start; there a PCM software update was the remedy, with a check-engine lamp as the complaint. As a reference for the electrical limit, a Saab 9-5 brake unit treats anything under 0.25 V lasting 0.1 s as a sensor fault. Signal shorts to ground, a missing 5-V feed or a failed sensor are the usual causes.
- What you may notice
- Check-engine or ESC warning lamp on
- Adaptive cruise control or stop-start unavailable
- Likely causes
- LikelySignal line shorted to ground
- PossibleSensor or the ESC unit with integrated sensor defective
- PossibleEngine control software misjudging the signal (Jeep Cherokee 2019)
- Rare5-V sensor supply dragged down
- Repair
- Medium · Usually a job for a workshop.Typical cost: €60 – €2,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.