Prius Remote Car Start Detection

Not sure if this is the proper place to post this, but I’m wondering if anyone out there can think of a smart solution to a problem.

We picked up a Prius Prime at a good deal this summer. Much to our surprise, the interface and software design is poor. In particular, we can’t tell if the car is remotely started because it’s so quiet and there’s no indicator that the car is turned on. The Toyota app EnTune is also unreliable.

Possibilities for HE:

  1. vibration detection?
  2. airflow/vent detection?
  3. car computer code reader?
  4. noise detection? (Probably would be falsely triggered.)

Accessories turned on, when you turn on the car the 12v accessories will be powered on, you could add a 12v to 3v converter and connect maybe an arrival sensor, then create a rule when this sensor arrives to send you a notification "Prius Prime Powered" or anything. I think it's the easiest way and more reliable than vibration, airflow, noise and less complicated than code reader using obd2

Good luck


Great idea actually and wish I had thought of it. My wife just informed me that the Prius accessories (to the best of her knowledge) do not turn on with remote start. This even includes the car seat warmers...

On the other hand, our older Scion battery will start with accessories but the engine doesn’t always turn over... (another car that could use remote start detection.)

You guys suppose a remote temperature sensor placed in each car cabin could work?
Let’s say if the sensor reports a temperature rise within a couple of minutes, it would send an alert stating that the cars turned on? I’d prefer something more responsive and plus would it be an issue having these sensors continually leave and enter hub range?

Should be something turning on in 12v, but anyway this suggestion needs some technical knowledge and I'm not sure if you are able to do this, but any place that they install aftermarket alarms or radios will help you to get those 12v

Maybe if you park it somewhere that the ambient temperature never changes...

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Do the USB ports energize when the car is started? If so you could use this or one of the other examples in this thread.

The temps would need to change rapidly in a short amount of time, but I’d also need a sensor that would poll frequently too without blowing through batteries.

It’s one of the full digital screens so I don’t think too many people replace that and it stays off when remotely started. Only thing that comes on afaik is an interior fan. In colder weather, the Prius Primes rely on gas to heat otherwise it’s taxing on the batteries. In my Scion, I wired up a rear view camera to the brake lights and it was pretty simple. With this car, all I can see is one quick brake flash when you press the remote and that’s all.

Will check.