OBD-II code · Powertrain (generic)

P0559 Brake Booster Pressure Sensor Circuit Intermittent

Same as P0555 with intermittent or erratic signal. Boost control tracks commanded vs. actual manifold pressure; persistent deviation means wastegate, vanes, hose or actuator are not delivering the requested pressure.

Is it safe to drive with P0559?

Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.

Common causes

  • Most likelyIntermittent contact at connector
  • Less likelyConnector with intermittent contact under vibration
  • Less likelyHarness routed against vibrating component

Symptoms

  • Check engine light on
  • Significant power loss / limp mode
  • Possible blue or black smoke from exhaust
  • Whistling or hissing sound from intake

Repair at a glance

Difficulty
Easy
DIY friendly
Often, with basic tools
Typical labour
0.4–1.4 h
Emissions test
Usually unaffected
Parts involved
Brake Booster Pressure Sensor, Brake Booster Wiring

Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.