P2626moderate severityPowertrain
O2 Sensor Pumping Current Trim Circuit Open Bank 1 Sensor 1
on 1998 BMW 528i 2.8L I6 M52 · RWD
What this code means
Open circuit in the wideband O2 sensor trim circuit on bank 1.
Symptoms
- Check engine light
- Poor fuel economy
- Rough running
Common causes
- Failed wideband O2 sensor
- Wiring damage
- ECM circuit fault
Diagnostic steps
- Check sensor connector
- Measure sensor heater and signal circuits
- Inspect wiring
Repair notes
Replace wideband O2 sensor. Verify wiring.
🔌 Don't have a code reader?
Any of these will read and clear this code — pick by how deep you want to go.
Bluetooth code reader (~$25)
Veepeak OBDCheck BLE →
Pairs with your phone — reads and clears codes, live data.
Serious DIY (~$100)
BlueDriver Pro →
Enhanced codes (ABS, airbag, TPMS) plus repair reports.
Shop-grade tablet (~$300+)
Autel MaxiCOM MK808S →
Bidirectional tests, service resets, all systems.
As an Amazon Associate, OLP earns from qualifying purchases — how we link. This never changes the specs we publish.
Other Powertrain codes on this vehicle
29CC
Misfire Cylinder 1
29CD
Misfire Cylinder 2
29CE
Misfire Cylinder 3
29CF
Misfire Cylinder 4
29D0
Misfire Cylinder 5
29D1
Misfire Cylinder 6
29D2
Misfire Cylinder 7
29E0
Lambda Additive/Idle Adaptation Limit, Bank 1
29E1
Lambda Additive/Idle Adaptation Limit, Bank 2
29E2
Lambda Multiplicative Part-Load Adaptation Limit, Bank 1