P209A

Reductant Injection Air Pressure Sensor B Circuit

Severity

⚠️ Medium

Can you drive?

Yes, but get it checked soon

Approx. repair cost

$28–89 (est.)

Symptoms

Check Engine light comes on
Reduced engine power
Increased fuel consumption
Unstable engine operation
Increased emissions

Causes

Open or short circuit in the sensor circuit
Air pressure sensor B fault
Wiring harness damage
Problems with the engine control unit
Dirty or clogged air passages

How to Fix

Check the integrity of the sensor circuit
Check sensor resistance and voltage
Inspect the wiring harness for damage
Clean the system air passages
Replace air pressure sensor B if necessary

Related codes

P209B P2099 P20EE