OBD-II Code P2626 — What It Means & How to Fix It

What it means

P2626 means there is an open circuit in the pumping current trim circuit for the Bank 1 Sensor 1 wideband oxygen sensor.
The sensor cannot fine-tune its oxygen measurements, leading to inaccurate readings and poor fuel trim control.
You may notice poor fuel economy, rough running, or failed emissions testing.

Affected Models

All vehicles 1996+ with wideband O2 sensors
Common in vehicles with direct injection engines
Common in European vehicles (BMW, Mercedes, VW/Audi)
Common in Honda and Toyota vehicles

Common Causes

Failed wideband O2 sensor with an open internal trim circuit
Open wire in the trim circuit between the sensor and ECM
Corroded or damaged sensor connector pin
Contaminated sensor from oil or coolant in the exhaust
Age-related sensor degradation — wideband sensors wear over time

How to Fix It

Scan for all codes — look for fuel trim and other O2 sensor codes alongside P2626.

Codes like P0171 (lean bank 1) or P0130 (O2 sensor circuit) alongside P2626 confirm the sensor is affecting fuel control.
Inspect the sensor wiring harness connector for damage or corrosion.

The connector is exposed to exhaust heat — pin corrosion and wire insulation damage are common failure modes.
Check for exhaust leaks near the sensor that could contaminate it.

An exhaust leak upstream of the sensor introduces fresh air into the exhaust stream, skewing sensor readings and causing premature failure.
Test continuity of the trim circuit wires from sensor to ECM.

An open trim circuit wire will show no continuity — trace the wire to find any breaks or damage.
Replace the wideband O2 sensor — internal trim circuit failures require full sensor replacement.

Wideband sensors cannot be repaired — if the internal trim circuit is open, the sensor must be replaced with a quality unit.

When to Call a Professional

A failed wideband O2 sensor affects fuel trim and emissions — the vehicle may fail an emissions test.
A technician will scan for fuel trim codes, inspect the wiring, and test sensor function with a wideband-capable scan tool.
Wideband sensor replacement typically costs $150–$350 including labor.

Frequently Asked Questions

What is a wideband O2 sensor?

A wideband sensor can measure oxygen levels across a much wider range than traditional narrowband sensors.
They are used in modern vehicles for precise fuel control, especially in direct injection engines.
They have more internal circuits, which means more potential failure points.

How much does a wideband O2 sensor cost?

Wideband sensors are more expensive than traditional narrowband sensors.
Expect to pay $80–$250 for the part depending on the vehicle.
OEM or OEM-equivalent sensors are strongly recommended — generic sensors may not be properly calibrated.

Can I use a generic O2 sensor for P2626?

It is not recommended.
Wideband sensors require precise calibration that many generic aftermarket units do not meet.
Using an incompatible sensor can cause additional fault codes and incorrect fuel trims.
Stick with OEM or a reputable brand like Bosch or Denso.