Camshaft Position Sensor B Circuit High (Bank 2)
The P0393 code means the vehicle's onboard diagnostic system has detected: Camshaft Position Sensor B Circuit High (Bank 2). This is a moderate severity code.
- Keep driving?
- Short distances only
- DIY difficulty
- moderate
- Estimated cost
- $60 - $350 (parts and labor)
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Common Symptoms
- Check Engine Light on
- Bank 2 engine performance issues
- Hard starting
- Possible stalling
Probable Causes (Ranked by Likelihood)
- Open circuit in cam sensor B wiring Very High
- Failed sensor (open) High
- Disconnected connector Moderate
- PCM input open Low
Frequently Asked Questions
What does circuit high mean for cam sensor B?
An open wire or disconnected sensor causes the signal to float high, indicating no valid signal to the PCM.
Can a disconnected connector cause P0393?
Yes, this is a common cause. Verify the connector is fully seated before replacing the sensor.
Will the engine start without this sensor?
Most engines will start using other sensor signals in degraded mode, but performance will be reduced.
Mechanics Guide Step-by-step diagnosis
Step-by-Step Diagnostic Procedure
-
Check connector is seated.
-
Measure sensor resistance.
-
Test wiring continuity.
-
Replace sensor if open.
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
Commonly Affected Vehicles
- 2010-2020 GMC Acadia (3.6L V6)
- 2012-2019 Buick Enclave (3.6L V6)
- 2008-2018 Toyota 4Runner (4.0L V6)
- 2011-2020 Jeep Grand Cherokee (3.6L V6)
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