P2A39

O2 Sensor Positive Current Control Circuit Low Bank 1 Sensor 3

Severity

⚠️ Medium

Can you drive?

Yes, but get it checked soon

Approx. repair cost

$17–56 (est.)

Symptoms

Check Engine light comes on
Reduced engine power
Increased fuel consumption
Unstable engine idling
Problems with passing technical inspection

Causes

Open or short circuit in O2 sensor control circuit
Oxygen sensor malfunction (bank 1, sensor 3)
Problems with the engine control unit (ECU)
Corroded or damaged wiring connectors
Low voltage in the vehicle's electrical system

How to Fix

Check the continuity of the O2 sensor control circuit
Inspect connectors and connections for corrosion or damage
Check the functionality of the oxygen sensor (bank 1, sensor 3)
If necessary, replace the oxygen sensor
Check the condition of the engine control unit (ECU)

Related codes

P2A3A P2A3B P2A3C