Turbo/Super Charger Boost Sensor "B" Circuit
The P0239 code means the vehicle's onboard diagnostic system has detected: Turbo/Super Charger Boost Sensor "B" Circuit. This is a moderate severity code.
- Keep driving?
- Short distances only
- DIY difficulty
- moderate
- Estimated cost
- $80 - $350 (parts and labor)
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What Are the Symptoms of P0239?
- Check Engine Light on
- Reduced power or limited boost
- Possible hesitation under acceleration
What Causes P0239? (Most Likely First)
- Failed sensor High
- Open or shorted wiring in the sensor circuit High
- Loose or corroded connector Moderate
- Engine computer input fault Low
Can I Still Drive with P0239?
Short distances only. P0239 is rated moderate severity. Keep trips short and get it diagnosed soon rather than waiting for symptoms to worsen.
Frequently Asked Questions
What does P0239 mean?
P0239 means Turbo/Super Charger Boost Sensor "B" Circuit. The engine computer has detected an electrical fault in the circuit for boost pressure sensor "B".
Can I drive with this code?
Usually for short distances, but the engine computer may limit boost, so expect reduced power until it is repaired.
Mechanics Guide Step-by-step diagnosis
How Do You Diagnose P0239?
-
Find which sensor is "B" on your engine in the service information. The letter is set by the manufacturer.
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Inspect the sensor connector and harness for damage, corrosion or oil contamination.
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Check the sensor's reference voltage, ground and signal on a scan tool or meter, and compare with the service specification.
Sources 2
This page is built from documented references. Verify against your own service info before repair work.
- SAE J2012Diagnostic Trouble Code Definitions (defines the generic OBD-II code ranges)
- Cross-checked against the SAE J2012:2002 DTC table (2026-08-27)archived scan of the SAE standard — readable copy, not SAE’s current edition
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