Camshaft Position Sensor B Circuit Intermittent (Bank 2)
The P0394 code means the vehicle's onboard diagnostic system has detected: Camshaft Position Sensor B Circuit Intermittent (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
- Intermittent Check Engine Light
- Occasional rough running
- Random hesitation
- Engine may stall in rare cases
Probable Causes (Ranked by Likelihood)
- Loose cam sensor B connector on Bank 2 Very High
- Intermittent wire break High
- Sensor failing under heat Moderate
- Vibration fault Low
Frequently Asked Questions
How do I catch an intermittent cam sensor fault?
Drive with scan tool recording. Wiggle the connector and wiring while monitoring the cam sensor signal for dropouts.
Can heat cause intermittent cam sensor problems?
Yes, cam sensors can fail when hot and work when cold. This is a common failure pattern.
Should I replace the sensor preventively?
If you have intermittent cam sensor codes and the sensor is original with high mileage, proactive replacement is reasonable.
Mechanics Guide Step-by-step diagnosis
Step-by-Step Diagnostic Procedure
-
Wiggle test on sensor connector while monitoring signal.
-
Inspect connector pins.
-
Check wiring at stress points.
-
Test during hot and cold operation.
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 Nissan Pathfinder (3.5L V6)
- 2012-2019 Infiniti QX60 (3.5L V6)
- 2008-2018 Mazda CX-9 (3.7L V6)
- 2011-2020 Ford Flex (3.5L V6)
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