CodeFix
ER04Breville

Breville / Sage Barista Touch ER04: temperature sensor short circuit

ER04 means: Ferro heater temperature sensor short circuit detected during operation.

Same code, same fix on the Barista Touch Impress. Everything below applies to both.

Applies to: Barista Touch.

Short answerThe ThermoJet (ferro) heater temperature sensor (NTC) is reading as a short circuit: the board sees near-zero resistance, which a healthy sensor does not produce. Technician sources name water bridging the sensor contacts (a leak or steam at the probe seal) and a failed sensor as the likely causes. Because it happened during operation, heat or steam reaching the connector is a plausible cause. Breville does not publish this code table, so the meaning comes from third-party service tables.
Part at faultThermoJet (ferro) heater temperature sensor (NTC)
Severitymedium
DIY difficultyhard
When it appearswhile brewing or steaming

How to fix ER04

  1. Switch off at the wall and unplug. Leave the machine for an hour so any moisture dries, then try again. A short that clears after drying suggests a leak to find.
  2. Inspecting the ThermoJet (ferro) heater temperature sensor (NTC) plug and the wiring near the boiler means opening the machine, which is technician work. A technician would look for a wet patch, white scale trails or a perished o-ring around the probe.
  3. A technician would replace any leaking o-rings at the boiler fittings and sensor probes; the leak, not the sensor, may be the true fault.
  4. If the code persists after everything is dry, the ThermoJet (ferro) heater temperature sensor (NTC) needs replacing by a technician.
  5. Afterwards, clear the error log and run a full heat-up and a shot to confirm.
Flowchart for fixing ER04: work through each step, stop as soon as the code clearsER04 appears1. Switch off at the wall and unplug.Fixed?yesDone2. Inspecting the ThermoJet (ferro) heatertemperature sensor (NTC) plug and the wiringnear the boiler means opening the…Fixed?yesDone3. A technician would replace any leakingo-rings at the boiler fittings and sensorprobes; the leak, not the sensor, may bethe…Fixed?yesDone4. If the code persists after everything isdry, the ThermoJet (ferro) heatertemperature sensor (NTC) needs replacing bya…Fixed?yesDone5. Afterwards, clear the error log and run afull heat-up and a shot to confirm.Still showing?If you see scorch marks, smell burning, orthe machine trips your GFCI / RCD, stop:that is an electrical fault, not just a…
The same steps as the list above, cheapest first. Stop as soon as the code clears.

When to stop and call a repairer

If you see scorch marks, smell burning, or the machine trips your GFCI / RCD, stop: that is an electrical fault, not just a sensor.

What it costs

PartsNot published by Breville. Ask an authorised service centre for a quote.
ServiceNot published by Breville. Ask an authorised service centre for a quote.
Worth repairing?Often yes, but Breville does not publish repair costs. If a leak has soaked the control board, get a quote before spending anything.

How to check the error log

Switch the machine off at the wall. Hold the front Power button, switch the wall power back on and release when the logo appears. Enter the service password 00000, then open Error Counter to see stored faults or Live Debug for live temperatures.

Clear the log after a repair so you can tell whether the fault has really gone.

Beyond the fix

Tips and tricks

  • Scale lowers flow and brewing temperature, according to the manual. Run the Descale Cycle from Settings with the machine cool and the drip tray empty, and never pull the tank mid-cycle.manufacturer manual

Further reading

Questions

What does ER04 mean on the Breville / Sage Barista Touch?

Ferro heater temperature sensor short circuit detected during operation. The ThermoJet (ferro) heater temperature sensor (NTC) is reading as a short circuit: the board sees near-zero resistance, which a healthy sensor does not produce. Technician sources name water bridging the sensor contacts (a leak or steam at the probe seal) and a failed sensor as the likely causes. Because it happened during operation, heat or steam reaching the connector is a plausible cause. Breville does not publish this code table, so the meaning comes from third-party service tables.

Can I fix ER04 myself?

DIY difficulty: hard. Switch off at the wall and unplug. Leave the machine for an hour so any moisture dries, then try again. A short that clears after drying suggests a leak to find. Inspecting the ThermoJet (ferro) heater temperature sensor (NTC) plug and the wiring near the boiler means opening the machine, which is technician work. A technician would look for a wet patch, white scale trails or a perished o-ring around the probe.

How much does it cost to fix ER04?

Not published by Breville. Ask an authorised service centre for a quote. Not published by Breville. Ask an authorised service centre for a quote.

Is it worth repairing?

Often yes, but Breville does not publish repair costs. If a leak has soaked the control board, get a quote before spending anything.

When does ER04 typically show up?

Breville / Sage Barista Touchs report ER04 while brewing or steaming. That timing is a useful clue when narrowing the cause.

Can I keep using the machine with ER04 showing?

Usually you can finish the drink you are making, but do not ignore it — the underlying fault rarely heals itself. Work through the cheap checks first.

Will ER04 clear on its own?

Rarely. A reset or power cycle is worth one try, but ER04 with a "hard" difficulty rating almost always means a failed component that has to be replaced.

How long does the repair take?

This one is a bench repair for most owners — the teardown, test and reassembly are the bulk of the work, not the part itself.

How reliable is this page?Breville and Sage do not publish a table of error codes for these machines in the documents we found. The meanings on this page come from third-party repair references and owner reports, so treat them as lower confidence. If your machine shows a text alert, follow the on-screen text first. Model revisions can differ: if your machine behaves differently, tell us. See our editorial policy.