Breville / Sage Barista Touch ER05: temperature sensor open circuit (not detected)
ER05 means: Milk jug temperature sensor open circuit detected at startup.
How to fix ER05
- Switch the machine off at the wall, wait 60 seconds and switch it back on. A one-off reading glitch clears; a real open circuit comes straight back.
- Look at the milk temperature sensor on the drip tray area. The sensor knob must sit vertically in its rubber mount and the metal contact pads must line up with the jug. Reseat it, clean the pads and try again. This alone fixes a large share of ER05 to ER08 reports.
- Check for water where it should not be. Moisture on the board or in a connector reads as an open or short. Dry everything and look for the leak that caused it (usually a boiler o-ring or hose clip).
- If the code returns, replace the milk jug temperature sensor (NTC). On the Barista Touch it is a plug-in part; note which way the wires route before pulling the old one.
- Clear the stored error afterwards (see how to read the error log below) so you can tell whether it recurs.
The five-minute check: pull the drip tray, look at the sensor knob. It must sit vertically in its rubber boot with the spring under it. Push it back in, wipe the three metal contact pads, refit and restart.
The real fix when reseating fails: the milk sensor wire. It fatigues where it flexes under the tray. Breville sells the NTC base assembly (genuine part around $80 to $95); third-party repair kits with a pre-fitted sensor and wire are $30 to $50. It is a 15-minute job with a Phillips screwdriver: five screws in the base, four on the sensor board, swap the wire, and line the jug pads up with the contacts before reassembling.
ER06, ER07 and ER08 are the same sensor reporting the fault at a different moment (open during operation, short at startup, short during operation). One kit fixes all four.
Breville out-of-warranty quotes for ER05 have been reported in the $150 to $250 range. Given the part cost, this is a repair worth doing yourself.
When to stop and call a repairer
Stop and book service if you find a swollen or burnt component on the board, or if the sensor plugs are fine and a new sensor does not clear the code: that points at the control board.
What it costs
Parts: Genuine NTC sensor assemblies run about $25 to $95 depending on which sensor it is (steam wand and milk-jug sensors are the dear ones). O-ring kits are $10 to $20.
Service: Out-of-warranty Breville service quotes for internal faults are commonly $300 to $500, sometimes more, plus shipping. Independent espresso repair shops are usually cheaper for a sensor swap.
Worth repairing? Usually yes. A sensor plus o-rings is under $100 and 30 to 60 minutes. Only a dead control board makes the repair questionable on an older machine.
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.
Related codes on the same part
- ER06 — Milk jug temperature sensor open circuit detected during operation
- ER07 — Milk jug temperature sensor short circuit detected at startup
- ER08 — Milk jug temperature sensor short circuit detected during operation
Same fault on other Breville / Sage machines
FAQ
What does ER05 mean on the Breville / Sage Barista Touch?
Milk jug temperature sensor open circuit detected at startup. The control board cannot read the milk jug temperature sensor (NTC). On this code the sensor reads as an open circuit: the wire has come off, the plug is loose or corroded, or the sensor itself has failed. Because it fails the self-test at power-on, the machine refuses to start until the sensor reads again. ER05 is the single most reported Breville Barista Touch error, and it is nearly always the milk jug temperature sensor: the small round probe on the drip tray that reads the jug temperature while the wand textures milk. The machine checks that sensor at startup, and if the probe wire has broken, the sensor knob has been knocked out of its rubber mount, or milk has got into the sensor cavity, the self-test fails and the machine stops at "ER05 startup error".
Can I fix ER05 myself?
DIY difficulty: moderate. Switch the machine off at the wall, wait 60 seconds and switch it back on. A one-off reading glitch clears; a real open circuit comes straight back. Look at the milk temperature sensor on the drip tray area. The sensor knob must sit vertically in its rubber mount and the metal contact pads must line up with the jug. Reseat it, clean the pads and try again. This alone fixes a large share of ER05 to ER08 reports.
How much does it cost to fix ER05?
Genuine NTC sensor assemblies run about $25 to $95 depending on which sensor it is (steam wand and milk-jug sensors are the dear ones). O-ring kits are $10 to $20. Out-of-warranty Breville service quotes for internal faults are commonly $300 to $500, sometimes more, plus shipping. Independent espresso repair shops are usually cheaper for a sensor swap.
Is it worth repairing?
Usually yes. A sensor plus o-rings is under $100 and 30 to 60 minutes. Only a dead control board makes the repair questionable on an older machine.
Code meanings are compiled from manufacturer service references and repair documentation for the BES880; fixes follow documented repairs and owner reports. Model revisions can differ. If your appliance is under warranty, contact the manufacturer before opening it.