What it means
Same as P2396 with the signal voltage above the plausible range. Wiring faults of this kind typically come from chafing, water ingress at connector seals, or pin push-back — a wiggle test on the harness while the code is active often confirms the location.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
The diesel intake air flow B position sensor reports where control valve B is positioned. The engine control module monitors its signal against the expected range; this code sets when the signal is too high, which can happen if it is shorted toward a supply voltage.
Common causes
Most likely first.
- Signal shorted to supply
- Connector pins corroded - high contact resistance
- Supply wire pinched against B+ source
Symptoms
- Check-engine light on
- Possible reduced engine power or sluggish response
How to diagnose it
- Check freeze-frame data and live position-sensor readings to confirm the fault is a high signal and note when it occurs.
- Inspect the B sensor connector and nearby harness for corrosion, water, pushed-back pins, chafing, or a wire pinched against a power source.
- With the signal visible on a scan tool, gently move the harness and connector to see whether the reading changes or the fault appears.
- Use the vehicle wiring diagram to check the sensor supply, ground, and signal circuit for shorts to voltage or excessive resistance.
- If the wiring tests correctly, compare the sensor output and valve position with the manufacturer's specification to identify a failed sensor or mechanical problem.
Common fixes
- Repair chafed or pinched wiring that is shorting the signal toward supply voltage.
- Clean and secure corroded or loose pins, and replace damaged connector terminals or seals.
- Repair an open or poor ground or supply connection found during circuit testing.
- Replace the B position sensor if its output remains too high with the circuit verified.
Can I keep driving?
If the engine runs normally, a short, cautious trip to a repair location is generally reasonable, but avoid hard acceleration if power is reduced. The fault can impair intake-air control and emissions, and the vehicle may become sluggish.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.