P0559
- Powertrain
- Generic (SAE)
- Safety
Stop driving
Continuing to drive risks injury or major mechanical damage. Shut the engine off when it is safe to do so.
Brake Booster Pressure Sensor Circuit Intermittent
This code is in our catalogue but has not yet been through editorial review, so the guidance below is limited to what our structured data supports. We publish deeper diagnostic content only after a code has been reviewed — here is why.
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.
A trouble code records what a control module measured. It does not identify which part failed. Test before replacing anything.
- Safe to drive
- Continuing to drive risks injury or major mechanical damage. Shut the engine off when it is safe to do so.
- Urgency
- Stop driving
- Will it pass emissions
- Not affected
- Check engine light
- Solid
- Significant power loss / limp mode
- Possible blue or black smoke from exhaust
- Whistling or hissing sound from intake
Many vehicles show no symptom at all beyond the warning light. The absence of a symptom does not mean the fault is not real.
| # | Cause | How often | Component |
|---|---|---|---|
| 1 | Intermittent contact at connector | Very common | — |
| 2 | Connector with intermittent contact under vibration | Occasional | — |
| 3 | Harness routed against vibrating component | Occasional | — |
Ordering reflects how often each cause is responsible in general, not a probability for your vehicle. Confirm by testing.
- Brake Booster Pressure Sensor
- Brake Booster Wiring
- Definition
- Generic code set (SAE J2012 / ISO 15031-6) via the OBDexopen database, dedicated to the public domain under CC0-1.0.
- Diagnostic guidance
- Written and reviewed in-house. See our editorial policy.
- Review status
- Awaiting review
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