Control panel displays ERR3 and grill will not maintain set temperature

Safety first: Unplug the grill before accessing wiring or the control panel.

• 1. Inspect the RTD probe:
  • Locate the metal temperature probe inside the cook chamber.
  • Ensure it is firmly mounted and not bent or broken.
  • Follow the probe wire through the wall grommet into the hopper/control area.
• 2. Check connections:
  • Remove the control panel mounting screws to access the back of the board.
  • Locate the RTD sensor plug (often a two-wire connector).
  • Unplug and re-seat the connector several times to clean contacts.
  • Look for corrosion, burnt pins, or loose terminals.
• 3. Test continuity (if you have a multimeter):
  • Disconnect the RTD from the board.
  • Measure resistance across the two RTD leads; typical values are 100–2000 Ω depending on sensor type and temperature.
  • An open circuit (OL) or 0 Ω indicates a failed probe.
• 4. Inspect wiring harness:
  • Check the harness from the probe to the board for cuts, pinch points, or melted insulation near hot surfaces.
  • Repair minor insulation damage with high-temp heat-shrink or replace the harness if conductors are exposed.
• 5. Replace faulty parts:
  • If the probe is open/shorted, replace the RTD temperature probe with a Masterbuilt-compatible sensor.
  • If a new probe does not clear ERR3, replace the control board.