Camshaft Position Sensor B Circuit (Bank 2)
The P0390 code means the vehicle's onboard diagnostic system has detected: Camshaft Position Sensor B Circuit (Bank 2). This is a moderate severity code.
- Keep driving?
- Short distances only
- DIY difficulty
- moderate
- Estimated cost
- $60 - $350 (parts and labor)
Best-selling code reader on Amazon. Reads and clears check engine codes on any 1996+ vehicle. Under $30.
Essential for diagnosing sensor codes, checking voltage, and testing circuits. Under $15 and pays for itself on the first job.
Affiliate links — we earn a commission at no extra cost to you.
Common Symptoms
- Check Engine Light on
- Engine may run rough
- Hard starting
- Possible loss of power
Probable Causes (Ranked by Likelihood)
- Faulty camshaft position sensor B (Bank 2) Very High
- Damaged sensor wiring High
- Corroded connector Moderate
- PCM input fault Low
Frequently Asked Questions
What is cam sensor B on Bank 2?
On engines with dual overhead cams, sensor B typically monitors the exhaust camshaft on Bank 2.
Is P0390 the same as P0345?
They are related but different. P0345 is a general Bank 2 cam sensor code, while P0390 specifically refers to cam sensor B on Bank 2.
Can I drive with P0390?
Short distances. The engine may have reduced performance but should run.
Mechanics Guide Step-by-step diagnosis
Step-by-Step Diagnostic Procedure
-
Check cam sensor B Bank 2 signal on scan tool.
-
Measure sensor resistance.
-
Inspect connector and wiring.
-
Swap sensors between banks if same part number.
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 Ford F-150 (3.5L EcoBoost)
- 2012-2019 Chevrolet Silverado (5.3L V8)
- 2008-2018 Toyota Tundra (5.7L V8)
- 2011-2020 Ram 1500 (5.7L HEMI)
Related Codes
Explore More
Was this helpful?
Send this to whoever is fixing the car — your mechanic, or the person asking what the light means.