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DTC code page

P0390: Camshaft Position Sensor B Circuit (Bank 2)

Quick answer: The ECU sees a fault in the Bank 2 camshaft position sensor B circuit or its signal quality.

Drivers also search this fault as bank 2 camshaft position sensor B circuit, bank 2 exhaust cam sensor code, cam sensor B bank 2 fault.

Severity: high Family: powertrain Related paths: 16
Meaning

What P0390 usually means

P0390 is the Bank 2 version of the camshaft position sensor B circuit fault. It usually points to the exhaust-cam or secondary cam signal on Bank 2, which makes it valuable when a V-engine has a one-bank startup, sync, or reduced-power complaint that does not fit a whole-engine sensor theory.

Fast triage

Start here before chasing parts

  • Scan first: save freeze-frame and pending codes before clearing anything.
  • Confirm the complaint: compare the stored code with current drivability symptoms.
  • Use context: trims, live data, and related codes usually narrow the fault faster than guesswork.
  • Work simplest to hardest: leaks, connectors, maintenance items, and known patterns before expensive components.
Initial checks

What to check first

  • Confirm bank orientation and sensor B location for the exact engine before replacing anything.
  • Inspect the Bank 2 sensor connector and nearby harness for oil, broken locks, or rub-through.
  • If P0019, P0345-P0349, or other Bank 2 timing clues are present, keep the one-bank timing branch active.
Driving risk

Can you keep driving?

P0390 can create long-crank, restart stall, or no-start behavior, so treat it as a high-priority drivability fault.

High urgency: If symptoms are active, reduce driving and diagnose quickly before secondary damage builds.
Likely causes

Common causes behind this code

  • Failed Bank 2 camshaft position sensor B
  • Connector or harness fault on the Bank 2 cam sensor B circuit
  • Oil intrusion or corrosion reducing signal quality at the connector
  • Mechanical timing drift or phaser trouble affecting Bank 2 exhaust-cam correlation
  • Low voltage or weak ground integrity during cranking

Cause phrases often tied to this code: bank 2 exhaust cam sensor, connector corrosion, timing drift bank 2, oil in cam connector, wiring damage near valve cover.

Diagnostic order

Suggested workflow

  1. Verify battery voltage and healthy cranking speed.
  2. Locate Bank 2 camshaft position sensor B and inspect connector, wiring, and mounting depth.
  3. Check scan data for unstable Bank 2 exhaust-cam sync during crank and hot restart.
  4. Test the sensor and circuit if the fault is not obvious from inspection.
  5. Inspect Bank 2 timing and phaser behavior if the electrical path checks out.
Avoid guesswork

Common mistakes

  • Replacing the wrong-bank sensor because Bank 2 location was assumed instead of confirmed.
  • Treating P0390 like a generic cam code and missing the one-bank clue.
  • Ignoring companion timing codes that suggest the signal problem may be mechanical too.
Repair path

Practical fix guidance

  • Fix the confirmed Bank 2 sensor, wiring, voltage, or timing issue first instead of replacing both exhaust-cam sensors on principle.
  • After repair, verify normal sync and restart behavior on repeated hot and cold starts.
Vehicle context

Affected brands in this MVP

Brand hubs help broaden internal linking now and can evolve into make-specific diagnostic notes later.

Aliases and common searches

English phrases tied to P0390

Useful when the driver knows the wording but not the exact DTC yet.

  • bank 2 camshaft position sensor B circuit
  • bank 2 exhaust cam sensor code
  • cam sensor B bank 2 fault
Related search intent

Queries this page can answer naturally

  • P0390 code meaning
  • what does P0390 mean
  • bank 2 cam sensor B symptoms
  • bank 2 exhaust cam sensor circuit
FAQ

Quick questions about P0390

Is P0390 the same as P0345?

Not exactly. P0345 is Bank 2 sensor A, while P0390 narrows the fault to sensor B on Bank 2.

Can P0390 cause a no-start?

Yes on some engines, especially when the ECU depends on that Bank 2 exhaust-cam signal for startup sync.

Does P0390 always mean the sensor is bad?

No. Wiring, oil-soaked connectors, low voltage, and Bank 2 timing issues can all trigger it.