Automatic Headlights

Perhaps Toyota saved a dollar or two by designing a "USA" (no fog, no auto)
Headlight Stalk, and eliminating a few cents worth of other parts?

Or, maybe they had some other "regulations" problem in the US?
But, the feature is available in other Toyota models?

 

Any progress on a source for the proper crimp-on pins?

Has anybody done the one-switch-not-stalk modification?

 

Back when I was doing this mod, I spent several hours on Mouser.com looking for a fit. I couldn't find one. These pins are made for Toyota by Tyco Electronics. (Was able to determine that by markings on the housing.) And while the connector "shell" is a standard part, the pins themselves are proprietary and restricted, meaning you can't even get data sheets for them.

I'm sure you could find a pin that would fit, if you modified (read: damaged) the connector housing - but I didn't want to do that. I was able to scavenge pins as described.

Sorry for not having better news... The good news is that the mod continues to work beautifully.

 

L8 is easily accessible. See the thread for details and photos of where it was on my IV (+NAV, no sunroof). It was just "hanging" behind the panel that holds the dash illumination "wheel" and mirror controls. On other models, it may be plugged into the ECU/Junction block, right underneath L7. My ECU doesn't even have a receptacle for it there - so it was simply hanging unplugged behind the panel (along with a couple of other unused connectors.)

Hope this helps.

 

Has anyone done this (jayvee's) auto headlight mod on a model V?

 

Or, on a model III ?

 

Well I have answered my own question. Yes, I have done the auto headlight mod on a model V with the AY package and it works.

The following is a statement of what I did with my own car and it is not a recommendation, of any kind, for anyone to do this with their car.


I went with a switch to ground the "Auto" signal instead of a new stalk.

Since I have a model V, I cannot use L8 for a source of pins. In fact I didn't use any pins when wiring L7. I found some 22 gauge wire with an insulation diameter that provides for a firm fit in the wire side connector openings. I stripped the wire back about 5/16 of an inch. I left the strands straight. I did not twist them together. I slid the wire into the "wire side" openings (rectangular holes) and all the way in until the wire strands stopped against the "pin side" of the connector. With the two wires, one for Auto select and the other from the light sensor, in place I plugged L7 into the ECU. After I restored battery power everything worked great.

One thing I noticed, since I have a separate switch for selecting Auto headlights, is that if I have Auto selected with the car off and I select the manual headlights via the stalk the headlights will not come on. I have to turn off the Auto switch first. However if the car is on with Auto selected and it’s during the day I can turn the headlights on manually.

 

Judgeless: I noticed that the photo cell that you used is not like the one provided in the 545T Nite-Lite System. Could you provide the make, model, and source for the photo cell you used? Thanks.

 

That is the one that came in my kit.

 

My last car was a Corolla which I had for 5 years. You get so used to the controls. It had auto headlights and daytime driving lights

I have driven several times without my lights on. I think what throws me off is the dashboard is all lit up. There are stretches of roads here that lights are required.

Thought it was pretty standard these days. It does affect your car insurance rates.

 

I also have a V with the AT package and would like to do the mod..... how did you wire it in and what switch did you use?

 

Start with this post (#88), and work your way forward in the thread. You first need to add a wire to the light sensor on the top of the dash - this is described in post #88:

http://priuschat.com/forums/gen-iii.../64812-automatic-headlights-9.html#post953788

 

Hi dwhutch,

Can you give more information on your installation process for the Prius V AT? Did you have to run a separate wire from the light sensor or was there already one there? The GPS knows if it's dark so I assume there's a wire down there somewhere.

what kind of switch did you use? can I get just a stand-alone switch that installs in the blank switch panel?

thanks.

 

There is no wire from the light sensor. The additional wire has to be installed. Jayvee, in this thread at post 88, documented the install with very good photographs so I could see what was under the dash. I studied the pictures and using a long pair (12 inches) of straight hemostats and after removing the glove box and the ECU cage behind it, was able to pop the sensor out through the top of the dash by squeezing on the sensor’s side tabs. This takes some patience and took over an hour to do. The cable on the sensor has just enough length so you can get to the connector and install the new wire. Getting to the sensor is the hard part, after that it's down hill. Running the wire to the Main ECU and installing a switch is easy. I installed a switch into one of unused switch panels. You can use any small toggle or pushbutton (push on/push off) switch. You are just grounding a signal so no high current to worry about. Just make sure the body of the switch is no wider than a half inch since that's about all the room you will have in the blank panel.

 

then, the only to do is:
L7,PIN21 TO I1,PIN4
and
L7,PIN28 TO SWITCH TO GROUND.

is it correct?
Thx.

 

Yes, That is correct. Be aware of the following:

"One thing I noticed, since I have a separate switch for selecting Auto headlights, is that if I have Auto selected with the car off and I select the manual headlights via the stalk the headlights will not come on. I have to turn off the Auto switch first. However if the car is on with Auto selected and it’s during the day I can turn the headlights on manually."

Since I used a stalk switch, I didn't have to worry about this issue.

 

This is because two ground connections.
At the day: auto on, but not connection, then you can put manual to on (1 ground).
in the night: auto on, connection on (1 ground). the manual cannot put lights off.
The stalk make 1 ground only, auto, on, off.

¿is the I1 signal special? that is a fotoswitch open/closed or it is a electronic circuit with special signal? I you wired to ground L7PIN21 directly it runs?
is there easy way to access I1 without dismanteling console?
THX.

 

Not exactly. It is in how the ECU is programmed to act on the individually grounded lines, headlights vs. auto on. The stalk grounds them separately - never at the same time. But it is the ECU and its software that is actually closing the relays, not the grounds of the switch lines. The ECU could have been software coded to ignore the "auto" line if the headlight line went to ground - it just wasn't, since Toyota didn't design the stalk that way.

It is an electronic circuit with special signal. Not just open/closed. It is a square wave that changes frequency with a change in daylight.

No, it will not.

It can be done by dismantling only part of the instrument panel. See dwhutch's post, 4 posts back.

 

How many wires has the I1 sensor from factory?
I have electrical wiring prius 2010 diagrams and must have 3 wires only to the ECU.
THX.

 

There are three wires already there - pins 1,3, and 6. Those three wires are shown on the air conditioning schematic/wiring diagram. The 4th wire (pin 4), which needs to be added, is shown on the headlight schematic. This 4th wire is only present in models outside the USA that have the Auto headlight option (such as Canada.)