Tesla update cuts third-party car-to-home power in Australia

Tesla software from the 2026.38 branch is cutting off third-party bidirectional discharge in Australia, according to an Australian owner and electrical engineer, Mark Purcell. Cars that were powering a home through a third-party charger now stop supplying power, and the older workarounds no longer help.

What owners are reporting

Purcell says his Model Y ran his house on 12 October through a Sigenergy charger, supplying about 25 kW. Since the 2026.38 software has been rolling out, he reports two failure patterns: a battery management alert that ends the supply roughly three minutes in, or a cut-off that arrives once 15 to 20 minutes have passed, no matter how heavy the load is.

The Camp Mode and Service Mode workarounds that owners used before no longer keep the link alive. Tlyard, another third-party charger maker, has warned that the power link may be cut, because Tesla software is able to spot charging that is being simulated.

Tesla's release notes for the update mention minor fixes only. Nothing in them says discharge is being switched off, so the cause is Purcell's account and that of the charger makers rather than anything Tesla has confirmed.

The warranty position

Tesla Australia's owner's manual says: "Do not use the Battery as a stationary power source. Doing so voids the warranty." That wording puts third-party home-powering setups on shaky ground whatever the software does.

The contrast with the US and Canada

The same 2026.38 branch brought Powershare with Powerwall home backup to the US and Canada. In Australia, existing Teslas lack Powershare, which there is vehicle-to-load only. So the official route to powering a home from a car is available in some markets and not in this one.

What Purcell has done

Purcell has deferred Tesla updates and asked Tesla in writing to hold them. He has also lodged a complaint with the ACCC, Australia's competition and consumer regulator, under Australian competition and consumer laws. He points to Apple's A$9 million Federal Court penalties over its Error 53 repair-rights claims as a comparison. The Australian Electric Vehicle Association is also part of the discussion, and David Waterworth, who helped get the article published, said: "I am looking forward to the discussions around this topic".

What to do if you own one

• If you run a third-party bidirectional charger in Australia, check whether your car is on the 2026.38 branch before accepting the update.
• Do not rely on a car as your only home backup while this is unresolved.
• Keep a record of what your car did before and after the update, in case you need it for a complaint.
• Remember that deferring updates can mean missing other fixes and features.

The outcome of the ACCC complaint is not known. For now, owners with these setups should treat car-to-home power outside Tesla's own system as something that may stop working without warning.

Credit: original reporting by CleanTechnica.