P0427moderate severityPowertrain
Catalyst Temperature Sensor Low Input (Bank 1, Sensor 1)
on 2019 BMW 330i 2.0L I4 Turbo B48 · RWD
What this code means
The PCM detected an abnormally low signal from the bank 1 catalyst temperature sensor. This can indicate a short to ground or open circuit.
Symptoms
- Check engine light on
- Failed emissions test
- Low temperature reading
Common causes
- Faulty temperature sensor
- Short to ground in wiring
- Open circuit
- Poor connector contact
Diagnostic steps
- Scan and confirm P0427
- Check sensor signal voltage
- Inspect wiring for shorts
- Test sensor resistance
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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