Auto on headlights?

It's one thing that's missing and I'm surprised it's not standard since the LE trim has many driving aid features. Maybe it's to make the limited trim special?

 

That’s difficult to say for sure. In the Repair Manual (more info), the diagram of the exterior lighting system shows that there is an automatic light control sensor and associated wiring that would have to be added, but the headlight switch is the same except for the “AUTO” (rather than “DRL”) label.

The control is in the software on the main body ECU (multiplex network body ECU), and this is the tricky part: Toyota’s parts catalog and service publications don’t tell us whether there is any version of the main body ECU and its software that has the automatic light control feature and would also work properly, under normal and abnormal conditions, with the other ECUs and equipment on the LE AWD-e model.

 

Just to point out, the OP has LE AWD-e model, not Prius Prime LE. Yeah, one thing I miss on my 2020 PP LE switched from 2017 PP Premium (which is now XLE) is this auto headlight-on feature.

 

No Auto-On Headlights for you!

 

If I had the LE trim, I would leave the lights on day and night to be on the safe side because one night out of one thousand and one nights you forget to turn them on and then you get into an accident. In fact in Norway, the cars are required to have their lights on at all times, as the concept of day and night is ambiguous there.

 

I'm not sure in California weather it is necessary to have your lights on all the time. Are the headlights sealed? Or if one stops working in a few years, can you can open them and replace the needed part?

 

The light sensor on the dash has dual functions:
- Auto headlight on/off for car so equipped
- Part of the neural network for the climate control system

 

How does auto-off work if you don't have auto-on ?

 

My wife's 2017 trim two has this. As I recall, the lights turn themselves off some time after you turn off the car. But then to turn them back on, you have to manually turn them off and back on. Pretty silly, eh? (Edited to add the part about after turning off the car. Thanks, @Salamander_King.)

 

I though the auto off is only for the time after the car is shut off. Or does it actually auto off during daylight?

 

Just when the car shuts off. I didn't think to include that detail.

 

I've had just about every sort.

• Manual - yep, we've all had lots of them.
• VW early '70s turned Headlights off - but left parkers/side lights on.
• Renault I think it was did the same - but beeped if I opened the door to remind me they were on.
• Several cars had beepers which ... umm beeped ... when the ignition was turned off.
• And 2 which I had to turn the headlights ON - but turned them off automatically.
• And PRIUS - which is AUTO ON & OFF. Though - I leave them on PARK/SIDE most of the time during the day, so have to remember to turn the headlights ON if it gets dark [*].

[*] - I knew you'd ask why. It's because, for some dumb reason, the DAYLIGHT RUNNING LIGHTS only turn the FRONT lights on.

But driving on the Motorway most of my driving, I think it's more important to have the REAR lights lit - and PRIUS has such cool rear lights - so I put the PARK/SIDE lights on. They work AUTOMATICALLY - turn off when I park, start automatically when I start-up again.

+

 

My 2017 Two Eco ... has auto headlights.

When the auto headlights are turned on, they come on when dark and turn off when light, or just off when you turn off the car off.

This behavior can be seen when going through a long tunnel. Headlights come on after entering the tunnel and off again after exiting the tunnel.