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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What Are the Symptoms of P0393?
- Check Engine Light on
- Bank 2 engine performance issues
- Hard starting
- Possible stalling
What Causes P0393? (Most Likely First)
- Open circuit in cam sensor B wiring Very High
- Failed sensor (open) High
- Disconnected connector Moderate
- PCM input open Low
Can I Still Drive with P0393?
Short distances only. P0393 is rated moderate severity. Keep trips short and get it diagnosed soon rather than waiting for symptoms to worsen.
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
How Do You Diagnose P0393?
-
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
Which Vehicles Commonly Get P0393?
- 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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