Phantom Drain: Normal vs Broken

Few things unsettle Tesla owners more than opening the app and seeing the battery has dropped overnight. You didn't drive. The car didn't move. And yet the number is lower.

This is usually called phantom drain. Some of it is completely normal, some isn't. The confusion comes from treating it as a single issue, when really it's several different systems behaving exactly as designed. Phantom drain isn't energy leaking out — it's energy being used while the car is parked. Teslas don't shut down; they move between sleep states, and what stays active depends on settings, environment and how often the car is woken.

In mild conditions with no special features enabled, a healthy Tesla loses roughly one to three percent per day while parked — background systems like battery management and cellular connectivity quietly protecting the car. If you're in that range, nothing is wrong.

Where it climbs, something is being kept awake.

The biggest contributor is Sentry Mode — cameras and processing active to monitor surroundings can account for five to seven percent a day. Not a fault; simply the cost of turning the car into a security system. Frequent app checks also wake the car and prevent deep sleep. Cabin Overheat Protection and cold-weather battery conditioning add smaller, intentional amounts.

What actually looks abnormal.

Consistent losses above eight to ten percent per day — with Sentry off, the app untouched and moderate temperatures — is worth investigating. Usually the culprit is an external app repeatedly waking the car. True hardware drain is rare but real: a failing 12-volt system or sensor fault can prevent proper sleep, and shows up clearly in service diagnostics.

The simplest diagnosis is to remove variables: park for 24 hours with Sentry off, Cabin Overheat Protection off and no app access. If drain drops to a few percent, it was configuration or usage. If it stays high, look deeper.

Phantom drain isn't a flaw — it's a side effect of owning a car that never truly shuts down. Most of the time it's normal, sometimes it's a setting, very rarely it's a problem. Understanding the difference turns it from a source of stress into something predictable.