O2 Sensor Pumping Current Trim Circuit/Open Bank 2 Sensor 1
Code P2629 indicates an open or malfunction in the pumping current trim circuit of the oxygen sensor located on Bank 2, Sensor 1 (upstream of the catalytic converter). This circuit is part of the wideband air-fuel ratio sensor, which uses a pumping current to measure oxygen content. An open circuit prevents the sensor from accurately reading exhaust gases, leading to incorrect fuel trim adjustments and potential drivability issues.
01. Most Common Causes
- Open or shorted wiring in the O2 sensor circuit
- Faulty O2 sensor (Bank 2 Sensor 1)
- Corroded or damaged connector
- Blown fuse related to O2 sensor heater or circuit
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Poor fuel economy
- Rough idle or hesitation during acceleration
- Failed emissions test
03. Step-by-Step Diagnosis
Step 1: Use a scan tool to verify code P2629 and check for additional codes.
Step 2: Visually inspect the O2 sensor wiring and connector for damage, corrosion, or loose connections.
Step 3: Test the sensor's heater circuit and signal wires with a multimeter for continuity and proper voltage.
Step 4: If wiring is intact, replace the O2 sensor (Bank 2 Sensor 1).
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
You can drive short distances, but it may cause poor performance and increased emissions. Prolonged driving could damage the catalytic converter.
How much does it cost to fix?▼
Typically $150-$300 including parts and labor, depending on vehicle make and sensor accessibility.