Oven displays E3 and may not heat or may show erratic temperature behavior.

Safety first: Disconnect power at the breaker before working on wiring or boards.

Step-by-step checks:

• Wiggle test: With power off, inspect and gently move the sensor harness along its length to identify any loose or broken sections.
• Clean connectors: Disconnect the sensor plug and the board connector. Clean contacts with electrical contact cleaner and reconnect firmly.
• Continuity test: Check continuity from the sensor connector to the control board connector on each conductor. Repair any open or high-resistance paths.
• Board evaluation: If wiring and sensor are good but E3 persists, the control board's sensor input circuitry may be faulty.

When to replace parts: Repair or replace the sensor wiring harness if intermittent. If harness and sensor are good, replace the electronic oven control board.