P2399

Diesel Intake Air Flow B Position Sensor Circuit High

Severity

⚠️ Medium

Can you drive?

Limited driving only, diagnose soon

Approx. repair cost

$28–89 (est.)

Symptoms

Reduced engine power
Unstable idling
Increased fuel consumption
Check engine light comes on
Problems starting in cold weather

Causes

Air flow position sensor B malfunction
Open or short circuit in wiring harness
Poor contact in electrical connector
Air control damper/valve problems
Engine ECU malfunction (rare)

How to Fix

Check the condition of the air flow position sensor B
Check the integrity of the wiring harness and contacts
Test sensor resistance
Check the operation of the air control damper/valve
Replace sensor if necessary

Related codes

P2397 P2398 P2400