Boost Calibration High
Your engine's turbo boost pressure is reading higher than expected, like a tire gauge showing more PSI than it should. The ECU detected the turbocharger or supercharger is over-pressurizing the intake system.
The ECU monitors boost pressure via a MAP (Manifold Absolute Pressure) or dedicated boost sensor against calibrated maximum thresholds. When boost pressure exceeds the programmed limit for the current operating conditions, the fault is triggered. This protects the engine from over-boost damage and detonation.
| Parameter | Normal Range | Fault Condition |
|---|---|---|
| Boost Pressure | 0.5-1.2 bar above atmospheric (engine dependent) | Exceeds calibrated maximum threshold by sustained margin |
| MAP/Boost Sensor Signal | 0.5-4.5 volts proportional to pressure | Voltage reading indicates pressure above safety limit |
Code P1306 is a moderate fault. You can generally drive to a workshop, but avoid long trips or high-load driving (motorway, uphill towing) until it is diagnosed. If the code keeps returning after clearing, or if you notice the symptoms listed above worsening, do not delay professional diagnosis. Many moderate codes have multiple possible root causes — a mechanic with live OBD data can identify the exact fault more efficiently than part-by-part trial and error.
Once the fault is repaired, P1306 can be cleared using any OBD-II scanner. Connect the scanner, navigate to "Clear Codes" or "Erase DTCs," and confirm. The check engine light turns off immediately.
The code will return if the root cause was not actually fixed. The ECM re-detects the fault within 1–3 drive cycles and sets the code again.