Final rinse appears to be cold; dishes are not hot when exiting the machine.

Safety first: Disconnect power to the booster and dishwasher before testing heaters and probes.

• Measure rinse temperature: Use a calibrated thermometer at the dish surface exiting the final rinse to confirm actual temperature.
• Check booster operation: Verify that the booster heater energizes and reaches setpoint. Test elements and high-limits as described in earlier entries.
• Inspect temperature probe: Ensure the rinse temperature probe is clean and properly mounted. Replace if readings are inaccurate.
• Adjust rinse time: On programmable Insinger controls, confirm that the final rinse duration meets factory recommendations.