The P0438 trouble code is associated with Catalyst Temperature Sensor Circuit High in Bank 2, Sensor 1, indicating that the signal from the temperature sensor for the catalytic converter in Bank 2 is registering higher than expected.
P0438 Catalyst Temperature Sensor Circuit High (Bank 2, Sensor 1)
Code symptoms P0438.
1. Illuminated “Check Engine” or “Service Engine Soon” light on the dashboard.
2. Reduced engine performance.
3. Poor fuel efficiency.
This code is common in brands such as:: Chevrolet, Renault, Ford, Toyota, Nissan, Mercedes Benz, Honda.
Causes of the code P0438.
1. Faulty catalytic converter temperature sensor in Bank 2, Sensor 1.
2. Wiring or connector issues in the circuit of the temperature sensor.
3. Corrosion or damage to the wiring harness.
4. ECM (Engine Control Module) issues.
Code Solutions P0438.
1. Test and, if necessary, replace the catalytic converter temperature sensor in Bank 2, Sensor 1.
2. Inspect the wiring and connectors associated with the temperature sensor for any damage or corrosion and repair as needed.
3. Check the wiring harness for any damage and repair or replace as necessary.
4. If other potential causes are ruled out, consider diagnosing and possibly replacing the ECM.