P209C

Reductant Injection Air Pressure Sensor B Circuit Low

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
Problems with the SCR (AdBlue) system
Increased emissions

Causes

Air pressure sensor B fault
Open or short circuit in the sensor circuit
Poor contact in the sensor connector
Problems with the engine control unit
Dirty or damaged wiring harness

How to Fix

Check the integrity of the sensor circuit
Check sensor connectors and connections
Test air pressure sensor B
Replace sensor if necessary
Check and update ECU software if necessary

Related codes

P209A P209B P209D