Catalyst Temperature Sensor Circuit Range/Performance Bank 1 Sensor 1

Where it lives

For P0426, the part to look at first is the sensor named here. The description of P0426 puts it on bank 1.

Check these first

• Catalyst temperature sensor bank 1 sensor 1 reading outside its expected range
• A chafed or shorted wire in the bank 1 sensor 1 signal circuit
• Corrosion or water in the bank 1 sensor 1 connector
• A failed thermocouple inside the bank 1 sensor 1 body
• An exhaust leak ahead of the sensor skewing its reading

What to do next

1. Inspect the bank 1 sensor 1 connector for corrosion or water
2. Test the bank 1 sensor 1 signal and ground wires for opens and shorts
3. Read catalyst temperature live data on bank 1 sensor 1
4. Check for exhaust leaks ahead of bank 1 sensor 1
5. Replace catalyst temperature sensor bank 1 sensor 1 if it stays out of range
6. Clear the code and retest

Look up another code