P0435Catalyst Temperature Sensor (Bank 2)
A fault has been detected in the Bank 2 catalyst temperature sensor or its circuit.
Definition
The PCM monitors the Bank 2 catalyst temperature sensor to confirm converter light-off and guard against overheating on the cylinder bank opposite cylinder 1. P0435 is the general circuit-malfunction code — the Bank 2 counterpart to P0425 — set when the signal opens, shorts, or exits its valid electrical window. There are no driveability symptoms, but the MIL illuminates, Bank 2 catalyst temperature monitoring is lost, and the vehicle will fail an emissions inspection.
Common causes
- Heat-damaged wiring where the Bank 2 sensor lead crosses the exhaust
- Failed sensor element, open or internally shorted
- Corroded, loose, or backed-out connector terminals
- Harness chafed to ground along the transmission tunnel or frame
- ECM input circuit fault (rare)
Common misdiagnoses
- Bank 2 catalytic converter replaced for an electrical sensor fault
- Bank 1 sensor replaced because the bank locations were confused
- Oxygen sensors replaced instead of the temperature sensor
Troubleshooting steps
1.Locate the correct sensor
Confirm Bank 2 (the bank not containing cylinder 1) and identify its catalyst temperature sensor before replacing anything.
2.Inspect wiring and connector
Check the lead for melted or brittle insulation near the exhaust and the connector for corrosion or spread terminals.
3.Measure sensor resistance
Compare the element at a known temperature against the spec chart — and against the Bank 1 sensor, which should read nearly identical when cold.
4.Verify reference voltage and ground
With the connector unplugged and key on, confirm roughly 5 volts of reference on the signal terminal and continuity to ground on the return.
5.Monitor the PID through a warm-up
The Bank 2 catalyst temperature should start at ambient and rise in step with Bank 1; a frozen or pegged trace confirms the circuit fault.