Tesla owners in several countries reported that a software update disrupted the third-party equipment they use to power their homes, sometimes cutting off the connection after three minutes.
Here's what to know
Tesla's 2026.38 software branch, which was rolled out in October, appears to interrupt battery discharge through third-party equipment, affecting users of several equipment brands. Electrical engineer and Tesla owner Mark Purcell described the problem for CleanTechnica.
Purcell cited reports on the Tesla Motors Club forum that described shutdowns three minutes in and a battery warning message. Others reported outages at the 15- to 20-minute mark regardless of load.
One equipment supplier cautioned that "simulated charging" can be detected by Tesla's 2026 software, potentially causing a power disconnection, Purcell reported. Owners also said that workarounds using Camp Mode or Service Mode had stopped helping.
The update's release notes mentioned "security improvements" and minor fixes, with nothing about a change to third-party discharge.
More background
Purcell noted that U.S. and Canadian Tesla owners got Powershare-enabled Powerwall backup through the same update line. However, Tesla Australia said existing vehicles can't receive a Powershare retrofit, and Tesla Australia offers only vehicle-to-load use.
TCD Picks » Quince Spotlight
💡These best-sellers from Quince deliver affordable, sustainable luxury for all
On Oct. 12, Purcell's Model Y supplied about 25 kilowatts to his Sunshine Coast home through a Sigenergy bidirectional DC charger.
"Do not use the battery as a stationary power source," Tesla Australia's manual states. "Doing so voids the warranty."
The company's Australian warranty page carves out one exception: damage caused by chargers or adapters from other brands, according to Purcell.
What's being done?
Purcell paused software updates on both of his Teslas and told the company in writing that he won't install another one until it guarantees third-party discharge will still work. That trade-off means he's also skipping whatever fixes are bundled into those updates.
He also filed a complaint against Tesla with the Australian Competition and Consumer Commission, arguing the update runs afoul of the country's consumer protection rules, and brought the issue to the Australian Electric Vehicle Association, hoping the group adds its support.
The regulator identified "denying interoperability" as a practice capable of undercutting competition in digital markets, according to Purcell.
Purcell wants carmakers to spell out functional changes before an update ships plus rules that let a vehicle pair with whichever bidirectional charger its owner chooses.
If Tesla has a safety or engineering concern, he wants the company to explain it and consider options such as equipment from certified partners, limits on discharge, or a published technical standard other charger makers could build around.
His Model Y continues to power his house while updates remain deferred.
"No owner, in any country, should have to choose between a current car and a working home battery," he wrote.
Where can I learn more?
Powerwall owners have reported problems with their home battery systems, too.
• One said a remote update disabled one battery, leaving an installer bill.
• Another said a 24-hour outage stopped solar generation, forcing the home onto grid power.
• A third said server errors hindered battery control, reflecting their dependence on cloud systems.
• Tesla disabled a recalled Powerwall without notice, its owner explained, with service unavailable until February.
• An Arizona homeowner said Tesla disabled a Powerwall for safety, then scheduled service four months out.
Get TCD's free newsletters for easy tips, smart advice, and a chance to earn $5,000 toward home upgrades. To see more stories like this one, change your Google preferences here.
Cool Picks
