I've only driven my used 2010 Prius once at night (only had it for 5 days) - and I certainly noticed the console buttons lighting up like the console of a 747. Did not pay attention to the shift lever light, but was trying to figure out today how it comes on. I guess it comes on along with the console button internal lighting. Now, what puzzles me is that it is definitely not linked with having the headlights on, as I keep them on all the time, day or night. So - there must be a daylight sensor somewhere, right? Thanks, - Paul
I don't think the US models have a light sensor. There is a small lens on the passenger side of the dash near the window, which according to the owners manual is for auto headlights (not offered in the US), so I suspect there's nothing under the lens. You can adjust the interior light intensity using the thumb wheel to the left of the steering wheel (next to the exterior mirrors control), and if you roll it all the way up past the click, it will not dim the interior lighting when you turn on the headlights.
Just like Flaninacupboard has already done, I plan to have mine "wired" up to the existing sensor (lens circular button looking thingamajiggy) to enable auto-headlights thanks to this awesome thread ! It's one of those cool evolution/discovery threads so you may want to read it from the present to the past.
It's a good mod! If my company didn't take such a dim view of it's employees modifying fleet vehicles, I would have done this before I burned the first tank of gas in "my" G3. Why in the world the folks in Aichi didn't include this feature in the US models---especially since the photocell is already installed, is a mystery to me!!! !!!!
OP (original poster) here - I'm not concerned about auto-sensing headlights - don't need that as I always have the lights on (I believe in "daytime running lights.") The issue is: what is controlling, under different (day/night) lighting conditions, all other things being equal including the position of the dash dimmer control, the illumination of a.) the shift lever light and b.) the console control buttons. And believe me, I've tested all positions of the dimmer switch in the daylight, and neither the buttons nor the shift lever light turn on. Thanks, - Paul
I suggest you try covering the photocell looking circular button we discussed on this thread and see if that keeps your illumination from adjusting. If so, you have your answer. I read on one of these threads of a guy/gal that drove in a tunnel with headlights on and notice the illumination adjusting and was thinking it was the photocell that we are talking about. Good luck with your findings.
Originally it was because the U.S. models had HID headlamps, and there was a concern about cycling. Now that HIDs are gone, I'm not sure why we don't get auto headlamps. Tom
I assume you've also tested to see if the dimmer switch was in the fully up position, past the click, or not? The shifter is lit from the overhead console (not internally lit)--have you looked for the light source overhead?
Yes, tested past the detent in the dimmer switch, and also know where the light for the shifter is. What started this thread, was that there was NO LIGHT from the shifter light overhead. Anyway - did some more tests: First, before starting the car, I blocked the light sensor on the dash in front of the passenger seat. Then, I made sure the headlight switch was off. Started the car, and turned on the headlights. By golly, the shift lever light came on. Turning down the dash light dimmer did not change it (but the green LEDs on the AC controls did dim.) Then I un-blocked the sensor, and NOTHING CHANGED! The shift lever light stayed on, and the dash lighting switch/dimmer worked exactly as it should - no difference. Turning the car off, leaving, coming back & starting it again (daylight with headlight switch left on), and the shift lever light was on. Turning headlights off caused it go turn off. Headlights on, it came back on. I'm sure this is the way it's supposed to be, totally independent of the sensor and controlled only by whether or not you have the headlights on. Why it wasn't working until I blocked the sensor, I don't know.
How long did you wait after you unblocked the sensor? I did the auto headlights mod and when I was testing it after I got it working it threw me off a little because there's a bit of a delay when the light input changes. If the headlights are off, but on auto (after the mod) and you block the sensor it takes about 30 seconds before the lights go on. Likewise, if the lights are on and you unblock the sensor it takes about 30 seconds before they turn off. This design makes sense if you think about it... you don't want your headlights coming on for a few seconds every time you drive under a bridge in the day, or turning off for a few seconds every time you drive under a street light at night. So the car waits for a little while to make sure that the light level really has changed before it activates or deactivates the headlights. I'm thinking that you might be seeing the same effect and you may need to wait 30 seconds or so after covering or uncovering the sensor to see any change.
I didn't necessarily wait more than 30 seconds after uncovering the sensor, but did perform several operations (turning lights off, back on, adjusting the dash brightness, etc.) Then I turned off the vehicle, exited, and WAITED UNTIL THE LIGHTS TURNED OFF (30 SECONDS) before re-entering and turning the car on. With headlights on, the shift lever light was also on. It goes out when the headlights are turned off. ***************************** OK - Mystery solved! I just performed more tests, and the sensor has nothing to do with the shift lever illumination. I did not notice that the light was on initially because I did not bend down and look directly into it. In bright light, you can't see any spill from the bulb on the recess housing it. So, I'm pretty sure I just thought it was off.
OK, that means it works with the dash board lighting. When you turn on parking lights, it also lights up.
Very true. Also, it does NOT change intensity with the dimmer switch (hey, it's just to create a glow on the shifter, so it's not that bright anyway!)
As for what the sensor's for - HVAC. Solar gain sensor allows the A/C to compensate for the sun beating down on the occupants.
Ok yeah so you've figured out that the ambient lighting (the one that shines on the shifter is on when the car's on?? The three buttons (EV, ECO, PWR) are illuminated when the door is opened (along with the POWER button, dome, personal and the footwell lighting). They're part of the illuminated entry system. I guess Toyota figures you might wanna choose one of those buttons when you start the car)
I didn't realize the Prius had that--a few of my previous cars had a sensor on the dash that sensed the sunlight direction, to adjust the A/C in appropriate sections of the car. The owner's manual says this about the sensor on the dash: Headlight control sensor (if equipped) The sensor may not function properly if an object is placed on the sensor, or anything that blocks the sensor is affixed to the windshield. Doing so interferes with the sensor detecting the level of ambient light and may cause the automatic headlight control system to malfunction.
The old Prius had 2 domes in Canadian models and one in US models (one for auto headlights and one for auto a/c). I don't know where the a/c sensor is on the Gen 3 since I only see one dome on my car (is there one on the US version? Is it empty or can you see some sort of circuit board inside?)
