P2628moderate severityPowertrain
O2 Sensor Pumping Current Trim Circuit High Bank 1 Sensor 1
on 1999 BMW 540iT E39 4.4L V8 · RWD
What this code means
High current in wideband O2 sensor trim circuit bank 1.
Symptoms
- Check engine light
- Lean running condition
Common causes
- Open circuit
- Failed sensor
- Short to voltage
Diagnostic steps
- Measure circuit current
- Check for opens
Repair notes
Replace sensor or repair wiring.
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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