Stero Dishwasher Error Code RINSE TEMP SENSOR: Service Required
RINSE TEMP SENSOR with Service Required and OPEN or SHORT on a Stero dishwasher means the final rinse temperature probe is out of range. The machine continues to run cycles. Contact your service provider; the service phone number is shown.
Medium: the machine runs, but it cannot confirm the final rinse temperature until the probe is repaired.
- Code
- RINSE TEMP SENSOR - Service Required - OPEN or SHORT
- Maker
- Stero
- Equipment
- Dish machines
- Applies to
- SU-L / SU-H undercounter (and SG glasswasher)
What does Stero RINSE TEMP SENSOR - Service Required - OPEN mean?
The final rinse probe reports the temperature of the last rinse water. That reading is what the control uses for the LOW RINSE TEMP checks. When the probe or its wiring is open or shorted, the reading falls out of range and the display shows RINSE TEMP SENSOR, Service Required, the service phone number and OPEN or SHORT. The machine continues to run cycles. The significance goes beyond a single sensor. Without a reliable rinse reading, the machine cannot warn about a cool rinse, so dishes may be rinsed too cool without any other message. The manual's action is to contact your service provider. The OPEN or SHORT wording shows the type of problem, and a technician checks the probe, the lead and the connector.
Affected models and control systems
Stero dishwashers SU-L ML-130274, SU-H ML-130273, SG-40 and SG-42.
Code numbers and their meaning can change between control generations. We match the full model and control before acting on a code.
What you may notice
- RINSE TEMP SENSOR and Service Required show on the display
- The service phone number is displayed
- The machine keeps running cycles
- LOW RINSE TEMP never appears even when the rinse feels cool
Possible causes
Likely causes — what usually sits behind RINSE TEMP SENSOR - Service Required - OPEN on this control. A technician confirms which one it is before any part is replaced.
- A rinse probe plug loosened by spray and steam
- A probe lead worn where it runs near the rinse manifold
Safe checks before calling for service
- Note the text on the display, including OPEN or SHORT.
- Feel the dish racks coming out and note whether the rinse seems hot.
- Do not open panels or unplug the probe.
- Call the number on the display or call us.
How a technician diagnoses RINSE TEMP SENSOR - Service Required - OPEN
- Read the display and note OPEN or SHORT.
- Measure the rinse probe resistance.
- Inspect the lead and connector near the rinse line.
- Compare the reading with a thermometer on the rinse water.
- Check the rinse heating.
- Replace the probe or repair the wiring.
- The probe sits in a wet area near mains-powered parts, so testing it is not a task for dish-room staff.
- The final rinse is the last step for every rack, so the reading must be reliable before the machine is trusted again.
- A meter is needed to tell an open from a short, and a thermometer to confirm the corrected reading under a running cycle.
How RINSE TEMP SENSOR - Service Required - OPEN differs from similar codes
RINSE TEMP SENSOR is the probe problem for the final rinse, while LOW RINSE TEMP is a warning that the measured rinse was cool.
Technical reference
- Maker documentation
- Stero owner support
- Edition
- ST50406 (01/16)
- Models / control
- SU-L / SU-H undercounter (and SG glasswasher)
- Section
- Operation, DIAGNOSTIC / ERROR MESSAGES (manual p. 18)
- Checked
- October 2026
We use the maker's document to read the code and do not reproduce it. Always confirm the complete model and control before applying these steps.
Related Stero dish machine error codes
Why does a bad rinse sensor matter?
The control cannot warn about a low rinse temperature without a reading.
Does the machine stop?
No. It continues to run cycles.
Is it the same as LOW RINSE TEMP?
No. LOW RINSE TEMP means the reading was low; this message means the probe reading is out of range.
Need help with Stero RINSE TEMP SENSOR - Service Required - OPEN?
A technician confirms the cause on site and gives you the price in writing before any work starts.