C0636Brake Pressure Sensor G Circuit High
- Generic OBD-II code · Chassis
- Can trigger limp mode
- How the car detects it
- The voltage of sensor G sits above anything a valid pressure can produce. A Toyota patent shows how a brake gets seven pressure sensors: one for the accumulator, two for the master cylinder chambers and four for the wheel cylinders, all read by the brake ECU. If one of them stops delivering sensible values, that ECU de-energises every valve and motor, and the front wheels are then braked with boosted pedal pressure. Whether Toyota or anyone else calls one of them G is not published. Denso reserves 4.7–5 V as an upper fault band and describes how a missing sensor ground raises the line into that band. GM's 2019 EBCM sets its high codes for brake pressure sensors above 95.24 % of supply for 100 ms. Typical causes: short to 5 V or battery, open ground.
- What you may notice
- ABS/ESC warning lamp on
- Live data shows high pressure with the pedal released
- Brake assist and stability functions unavailable
- Likely causes
- PossibleSignal wire shorted to the 5 V reference or battery voltage
- PossibleOpen or high-resistance sensor ground lifting the output
- PossibleSensor G failed internally and driving its output to the top
- Repair
- Medium · Usually a job for a workshop.Typical cost: €50 – €1,600
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.