Chassis, generic

C064E Brake Pressure Sensor N Circuit High

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modePossible

The signal of sensor N is above its permitted maximum. What the brake does next is described well for truck EBS: WABCO checks every analog pressure sensor signal against its authorised values; if one is lost, the module may keep producing electrical brake pressure by auxiliary means with limited accuracy, and if electronic control is impossible the axle falls back on purely pneumatic backup braking. For digital sensors the equivalent of a high reading is often a value pinned at full scale or a fault flag; Pico Technology notes that SENT frames carry a status nibble with diagnostic information and a CRC the receiver checks. C064E has no documented user, and nobody publishes which sensor N would be. Likely: short to supply, lost ground, failed sensor.

Likely causes

Signal shorted to sensor supply or battery voltage
Open sensor ground
Sensor electronics reporting full scale or an internal fault

Symptoms

  • Brake or ESC warning lamp on
  • Less precise brake pressure control or pure backup braking

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€50–1,600
Time0.5–3 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

brake pressure sensor nsensor wiring

Related codes

C064DC064FC0650C0646C064AC0642

References: wabco-customercentre.com, picoauto.com.