P0240 moderate

Turbo/Supercharger Boost Sensor B Circuit (Bank 2)

The P0240 code means the vehicle's onboard diagnostic system has detected: Turbo/Supercharger Boost Sensor B Circuit (Bank 2). This is a moderate severity code.

My Garage →
Keep driving?
Short distances only
DIY difficulty
moderate
Estimated cost
$80 - $400 (parts and labor)
Recommended Tool
ANCEL AD310 OBD-II Scanner
ANCEL AD310 OBD-II Scanner

Best-selling code reader on Amazon. Reads and clears check engine codes on any 1996+ vehicle. Under $30.

Check Price on Amazon

Affiliate link -- we earn a commission at no extra cost to you.

Every Tech Needs This
AstroAI Digital Multimeter
AstroAI Digital Multimeter

Essential for diagnosing sensor codes, checking voltage, and testing circuits. Under $15 and pays for itself on the first job.

Check Price on Amazon

Affiliate link -- we earn a commission at no extra cost to you.

Common Symptoms

  • Check Engine Light on
  • Bank 2 turbo boost reduced
  • Power loss from Bank 2 cylinders
  • Possible limp mode on twin-turbo systems

Probable Causes (Ranked by Likelihood)

  • Faulty Bank 2 turbo boost sensor Very High
  • Wiring damage to Bank 2 boost sensor High
  • Boost leak on Bank 2 intake tract Moderate
  • PCM circuit fault for Bank 2 Low

Step-by-Step Diagnostic Procedure

  1. Read Bank 2 boost sensor PID on scan tool. Compare to Bank 1 at idle (should be equal at atmospheric).

  2. Inspect Bank 2 boost sensor connector and wiring for damage.

  3. Pressure-test Bank 2 intake tract for boost leaks.

  4. Measure sensor output voltage and compare to Bank 1 sensor.

Frequently Asked Questions

What is the Bank 2 boost sensor?

On twin-turbo engines, each turbocharger has its own boost sensor. The Bank 2 sensor monitors boost pressure from the turbo serving Bank 2 cylinders.

Can I drive a twin-turbo with P0240?

You can drive short distances, but the PCM may limit Bank 2 boost, resulting in uneven power delivery and reduced overall performance.

Is P0240 different from P0236?

P0236 refers to boost sensor B in general. P0240 specifically indicates the boost sensor circuit for the Bank 2 turbocharger on twin-turbo engines.

Sources

This page is built from documented references. Verify against your own service info before repair work.

Explore More

Search codes Vehicle-specific fixes Guides By make

Was this helpful?

Send this to whoever is fixing the car — your mechanic, or the person asking what the light means.

Browse by symptom → Read repair guides → Fixes by vehicle →