MechanicDB
Fault Family System: Chassis (C-Codes) 65 SAE Codes

Brake Pressure Sensor Circuit

Diagnostic & Technical Explanation
Code C0044 (Brake Pressure Sensor A) sets when one of the hydraulic pressure sensors used by the brake-by-wire or ESC module to monitor circuit pressure reports a circuit that is open, shorted, out of range, uncalibrated, or intermittent, or disagrees with a paired redundant channel. Modern brake-by-wire and multi-circuit hydraulic systems label each sensor with a letter (A, B, C...) for a different hydraulic loop or redundant channel, but the physical sensor design and diagnosis are identical across all of them: a failed piezoresistive sensing element, a corroded connector, or a pinched signal wire near the hydraulic block. Because these sensors feed the pressure-based braking model directly, an uncorrected fault can cause the module to fall back to a reduced-assist limp mode.

These 65 diagnostic trouble codes share one detection mechanism and one repair path, which is why MechanicDB groups them into a single authored fault family rather than repeating the same explanation 65 times.

Codes in this family (65)

CodeDefinitionRepair coverage
C0044Brake Pressure Sensor A4 ranked fixes
C0045Brake Pressure Sensor B4 ranked fixes
C0046Brake Pressure Sensor A/B4 ranked fixes
C053DBrake Pressure Sensor A Range/Performance4 ranked fixes
C053EBrake Pressure Sensor A Circuit Low4 ranked fixes
C053FBrake Pressure Sensor A Circuit High4 ranked fixes
C0540Brake Pressure Sensor A Circuit/Open4 ranked fixes
C0541Brake Pressure Sensor B Range/Performance4 ranked fixes
C0542Brake Pressure Sensor B Circuit Low4 ranked fixes
C0543Brake Pressure Sensor B Circuit High4 ranked fixes
C0544Brake Pressure Sensor B Circuit/Open4 ranked fixes
C0560Brake Pressure Sensor A Missing Calibration4 ranked fixes
C056BBrake Pressure Sensor A Intermittent/Erratic4 ranked fixes
C056CBrake Pressure Sensor B Intermittent/Erratic4 ranked fixes
C0571Brake Pressure Sensor C Circuit Low4 ranked fixes
C0572Brake Pressure Sensor C Circuit High4 ranked fixes
C0573Brake Pressure Sensor C Circuit/Open4 ranked fixes
C0574Brake Pressure Sensor C Circuit Range/Performance4 ranked fixes
C0575Brake Pressure Sensor D Circuit Low4 ranked fixes
C0576Brake Pressure Sensor D Circuit High4 ranked fixes
C0577Brake Pressure Sensor D Circuit/Open4 ranked fixes
C0578Brake Pressure Sensor D Circuit Range/Performance4 ranked fixes
C059BBrake Pressure Sensor B Missing Calibration4 ranked fixes
C059CBrake Pressure Sensor C Missing Calibration4 ranked fixes
C059DBrake Pressure Sensor D Missing Calibration4 ranked fixes
C059EBrake Pressure Sensor E Missing Calibration4 ranked fixes
C059FBrake Pressure Sensor E Circuit Low4 ranked fixes
C05A0Brake Pressure Sensor E Circuit High4 ranked fixes
C05A1Brake Pressure Sensor E Circuit/Open4 ranked fixes
C05A2Brake Pressure Sensor E Range/Performance4 ranked fixes
C05C4Brake Pressure Sensor F Missing Calibration4 ranked fixes
C05C5Brake Pressure Sensor F Circuit Range/Performance4 ranked fixes
C05C6Brake Pressure Sensor F Circuit Low4 ranked fixes
C05C7Brake Pressure Sensor F Circuit High4 ranked fixes
C05C8Brake Pressure Sensor F Circuit/Open4 ranked fixes
C05C9Brake Pressure Sensor Supply Circuit4 ranked fixes
C0634Brake Pressure Sensor A/B Correlation4 ranked fixes
C0635Brake Pressure Sensor G Circuit/Open4 ranked fixes
C0636Brake Pressure Sensor G Circuit High4 ranked fixes
C0637Brake Pressure Sensor G Circuit Low4 ranked fixes
C0638Brake Pressure Sensor G Range/Performance4 ranked fixes
C0639Brake Pressure Sensor H Circuit/Open4 ranked fixes
C063ABrake Pressure Sensor H Circuit High4 ranked fixes
C063BBrake Pressure Sensor H Circuit Low4 ranked fixes
C063CBrake Pressure Sensor H Range/Performance4 ranked fixes
C063DBrake Pressure Sensor J Circuit/Open4 ranked fixes
C063EBrake Pressure Sensor J Circuit High4 ranked fixes
C063FBrake Pressure Sensor J Circuit Low4 ranked fixes
C0640Brake Pressure Sensor J Range/Performance4 ranked fixes
C0641Brake Pressure Sensor K Circuit/Open4 ranked fixes
C0642Brake Pressure Sensor K Circuit High4 ranked fixes
C0643Brake Pressure Sensor K Circuit Low4 ranked fixes
C0644Brake Pressure Sensor K Range/Performance4 ranked fixes
C0645Brake Pressure Sensor L Circuit/Open4 ranked fixes
C0646Brake Pressure Sensor L Circuit High4 ranked fixes
C0647Brake Pressure Sensor L Circuit Low4 ranked fixes
C0648Brake Pressure Sensor L Range/Performance4 ranked fixes
C0649Brake Pressure Sensor M Circuit/Open4 ranked fixes
C064ABrake Pressure Sensor M Circuit High4 ranked fixes
C064BBrake Pressure Sensor M Circuit Low4 ranked fixes
C064CBrake Pressure Sensor M Range/Performance4 ranked fixes
C064DBrake Pressure Sensor N Circuit/Open4 ranked fixes
C064EBrake Pressure Sensor N Circuit High4 ranked fixes
C064FBrake Pressure Sensor N Circuit Low4 ranked fixes
C0650Brake Pressure Sensor N Range/Performance4 ranked fixes

What this page does not show

This page publishes the fault mechanism and the code index. The licensed dataset adds, for every one of the 15,886 codes, the full authored repair set (56,729 procedures in total) with the fields deliberately withheld here: