Chassis, generic

C0578 Brake Pressure Sensor D Circuit Range/Performance

Check engine lightOn
EmissionsNot relevant
Drive cycleRequired
Limp modePossible

For sensor D the range/performance check targets a signal that is electrically fine but implausible. In GM's 2016–2019 hybrid brake modules, where D measures left rear brake pressure, the zero offset is learned while the car is being driven above about 4.5 mph with the brake released and the hydraulic pump idle; an offset beyond ±1,500 kPa sets C0578 at once, Type A with MIL. To prove the repair GM asks for driving at roughly 37 mph for at least 5 s. Wheel pressure sensors can also be checked against each other when valves connect them to one common pressure, a method described in a Lucas/ZF patent that singles out the drifting sensor and its error. Likely causes are sensor drift, trapped pressure in the rear circuit or a ground offset.

Likely causes

Zero point of sensor D drifted
Pressure trapped in the rear circuit, e.g. sticking caliper or valve
Ground offset between sensor and brake module

Symptoms

  • Check engine light and brake warnings (GM hybrids)
  • Rear brake pressure shown although no brake is applied
  • Code sets again after a short drive

Repair estimate

DifficultyHardWorkshop job
Parts and labour€60–2,500
Time0.5–4 h

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

Parts involved

brake pressure sensor dbrake control module

Related codes

C0575C0576C0577C059DC0574

References: gsi.ext.gm.com, gsi.ext.gm.com, patents.google.com.