P0427
PowertrainCatalystmoderate severityCatalyst Temperature Sensor Low Input (Bank 1, Sensor 1)
What P0427 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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