Hobart dishwasher displays E12; final rinse temperature sensor error.

Safety first: Turn off power and allow the booster/rinse system to cool before servicing.

• Locate rinse sensor: Identify the temperature probe installed in the final rinse line or booster tank.
• Inspect connections: Check the sensor connector and wiring for corrosion, loose pins, or damage from heat or chemicals.
• Secure and clean: Reseat the connector and clean contacts with electrical contact cleaner if needed.
• Replace sensor if needed: If the sensor is cracked, swollen, or tests out of specification, replace it with the correct Hobart rinse temperature probe.
• Further diagnosis: If E12 persists with a new sensor, the control board may have a failed input channel and should be evaluated by a Hobart technician.