Hobart Commercial Dishwasher Error Code WASH TEMP SENSOR: Open/Short
WASH TEMP SENSOR with Service Required and OPEN or SHORT on a Hobart LXe dishwasher means the wash temperature probe is out of range. The machine continues to run cycles. Call service.
Medium: the machine keeps running without a valid wash temperature reading.
- Code
- WASH TEMP SENSOR - Service Required - OPEN or SHORT
- Maker
- Hobart
- Equipment
- Dish machines
- Applies to
- LXe Series
What does Hobart WASH TEMP SENSOR - Service Required - OPEN mean?
The wash tank has a temperature probe that tells the control how warm the wash water is. The control expects a reading inside a set range. If the probe circuit is open, as with a broken wire, or shorted, the reading falls outside the range and the display shows WASH TEMP SENSOR / Service Required (Service Phone Number) / OPEN or SHORT. The word OPEN or SHORT shows which way the probe has failed. The machine continues to run cycles, so it is not locked out, but the control no longer knows the true wash temperature and cannot hold it. Poor cleaning and unreliable sanitizing may follow. The manual's action is to call service, because the probe and its wiring sit inside the machine and the cause is not something the operator can see or adjust.
Affected models and control systems
Hobart LXe series: LXeC (ML-130191), LXeH (ML-130192), LXePR (ML-130193) and LXeR (ML-130194).
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
- WASH TEMP SENSOR Service Required on the display
- OPEN or SHORT shown beneath the message
- Wash results that look weaker than normal
Possible causes
Likely causes — what usually sits behind WASH TEMP SENSOR - Service Required - OPEN on this control. A technician confirms which one it is before any part is replaced.
- Wash temperature probe out of range
- Probe lead broken where it flexes near the tank
- Scale or water getting into the probe connector
- Probe element failing electrically
- Loose connector at the control board
Safe checks before calling for service
- Note whether the message says OPEN or SHORT.
- Write down the service phone number shown on screen.
- Do not open panels or pull at wires.
- Keep the machine running only if wash results are acceptable, and tell us the model.
How a technician diagnoses WASH TEMP SENSOR - Service Required - OPEN
- Read the display message to confirm OPEN or SHORT.
- Measure the probe resistance and compare with the maker's chart for its temperature.
- Inspect the probe lead and connector for damage or moisture.
- Check the signal at the control with the probe disconnected.
- Replace the probe or repair the wiring, then run cycles to check the reading.
- The probe wiring runs through a machine that carries 208-240 V and standing water.
- Resistance testing and comparison to a temperature chart need a meter and the maker's data.
How WASH TEMP SENSOR - Service Required - OPEN differs from similar codes
WASH TEMP SENSOR concerns the wash tank probe; BOOSTER TEMP SENSOR and RINSE TEMP SENSOR are the equivalent messages for the other probes.
Technical reference
- Maker documentation
- Hobart owner support
- Edition
- FORM 38435 (March 2014)
- Models / control
- LXe Series
- Section
- DIAGNOSTIC/ERROR MESSAGES (page 27)
- 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 Hobart dish machine error codes
Does WASH TEMP SENSOR stop the machine?
No. The machine continues to run cycles, but it cannot regulate wash temperature properly.
What do OPEN and SHORT mean?
Open is a break in the probe circuit, and short is a wire path that bypasses the probe.
Can I reset it myself?
The manual says to call service.
Need help with Hobart WASH TEMP SENSOR - Service Required - OPEN?
A technician confirms the cause on site and gives you the price in writing before any work starts.