Tesla alert code · Electrical system
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Tesla GTW_w018 alert: Electrical system power reduced
GTW_w018
Electrical system power reduced
Vehicle may shut down unexpectedly
Needs attention
Top line is Tesla's on-screen wording. The level is RideRite's own read.
2 / 23
Teslas on RideRite's tools that have logged GTW_w018
2
times it was recorded in all, as of September 2026
Short answer
The car cut power to some systems to protect its low voltage power supply and warned that it may shut down unexpectedly. Level: needs attention.
What GTW_w018 means
The car cut power to some systems to protect its low voltage power supply and warned that it may shut down unexpectedly. Tesla's internal name for this alert, GTW_w018_hvacLoadShed, shows it sheds climate-system load first. Tesla has not published a detailed description, and it is rare, mostly seen on older Model S and Model X. It is a symptom rather than a diagnosis: on the two cars we have seen it on, one had a dead 12V battery and the other had high-voltage battery isolation faults at the same moment.
What to do
- 1If it appears while driving, find a safe place to stop, since Tesla's own text warns the car may shut down.
- 2Look at the other alerts logged at the same time. They usually name the real cause, such as a 12V battery alert or a high-voltage battery alert.
- 3Book service promptly and ask for both the low voltage battery and the high-voltage system to be checked.
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Ongoing
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An email in plain English if GTW_w018 comes back or a new alert appears, plus slow tire leaks and battery drain while parked.
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Get it fixed
Want GTW_w018 looked at without a trip to the service center?
Ride Rite is a mobile Tesla repair shop based in San Jose. We diagnose 12V and electrical warnings in your driveway or office lot across the Bay Area with dealer-grade diagnostic equipment, then tell you plainly what the car needs.
Common questions
Is GTW_w018 serious?
Treat it as serious. Tesla's own text warns the vehicle may shut down unexpectedly.
What causes GTW_w018?
Tesla has not published a cause. It appears when the car is short on low voltage power, which can come from a failing 12V battery or from a high-voltage battery fault that stops the car from supporting the 12V system. The alerts logged next to it are the best clue, and the free RideRite Health Check lists them with timestamps.
Related electrical system alerts
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See pricing and book onlineSources: the alert text and internal alert name your car reports to Tesla, Tesla's owner's manual where the code is listed, and alert records from Teslas connected to RideRite's tools.
All Tesla alert codes explained
Ride Rite Mobile Auto Services is an independent mobile Tesla repair shop in San Jose, California. Not affiliated with Tesla, Inc. General information, not a diagnosis of your specific car. Updated September 2026.
