C0635Brake Pressure Sensor G Circuit/Open
- Generic OBD-II code · Chassis
- Can trigger limp mode
- How the car detects it
- C0635 flags a broken circuit at brake pressure sensor G: a supply, signal or ground wire without continuity, or a plug that has lost contact. No manufacturer publishes C0635 in this meaning, so it is unknown which part carries the letter G. A seventh sensor only exists in large units, for example the Lucas/ZF electro-hydraulic layout with four wheel sensors, one supply sensor and two front push-through sensors. What the module reads after an open depends on its input: per Honeywell, losing feed or ground sends the signal to the top rail if the input is pulled up, to the bottom if it is pulled down. Saab/GM books such an interruption after 0.1 s and switches off ABS and stability control. GM's PIP5094 lists C0635 from an older, unrelated GM numbering.
- What you may notice
- ABS and ESC warning lamps on
- Stability control and pressure-based brake functions switched off
- Likely causes
- LikelyPlug at the sensor or hydraulic unit loose, corroded or with pushed-back terminals
- PossibleBroken supply, signal or ground wire in the sensor harness
- RareInternal interruption inside sensor G
- Repair
- Medium · Usually a job for a workshop.Typical cost: €40 – €1,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.