auto headlights-remote start

Hi all. 2007 Toyota 4runner and I just added Avital remote start. Vehicle has auto headlights. Did some research and it appears I need to install a relay so that the headlights automatically turn off when the remote starter shuts down. Unless you physically open the driver door, the headlights will stay on forever after remote shutdown. Can you tell me how to wire such a relay? thanks!

Well, you have a few choices. You can pulse the door trigger wire after a R/S shutdown or you can open the Auto-Headlights wire during a R/S. The problem comes in finding an Avital output that can do what you want, when you want it. Sometimes the (-) Rearm output connected to a typical N.O. Door Trigger wire will do the trick. Sometimes you might have to "strengthen" that Rearm signal with a relay. The way I like to do it is with a relay that is triggered by GWR or Status Output and opens the AutoHeadlight wire at the steering wheel headlight connector. On most Toyotas there is a (-) AutoHeadlight wire at that connector. It is usually right next to the (-) Parking Light wire. Test for this wire and then wire up a relay using the Avital 2nd Status Output wire like so : Relay Pin 85 to Avital 2nd Status Output Relay Pin 86 to +12V constant Relay Pin 87a to one side of cut AutoHeadlight wire Relay Pin 30 to the other side of the cut AutoHeadlight wire What happens : When a R/S is called for, the 2nd Status output comes on a second or two before the Avital starts turning on the ignition wires. The 2nd Status signal energizes the relay which opens the AutoHeadlight signal coming from the switch. If the headlight control switch was left at Auto, the (-) signal would not be seen or acted upon by the BCM, like it was never there, which in turn would prevent the headlights left on situation all together. At all other times, the headlight switch operates normally. Soldering is fun!

great thank you for such a detailed explanation. I also located the automatic light control sensor. Can I do something similar using the wires connected to that sensor? Rather than cutting the auto headlights wire could I cut one of the wires on the light control sensor and accomplish the same thing? Just a little nervous about cutting a main wire that controls the headlight in case the relay goes bad or the connections somehow work loose. thanks again.

Never tried it with the actual light sensor. It would have to be some kind of input to a logic circuit to know it's dark enough and that the AutoHeadlight function is ON. Personally, finding the AutoHeadlight wire at the headlight switch is much easier and more direct. Connections are not an issue there, where you can solder and use heat shrink tube. Relay failures are very rare, especially considering a simple ground signal is passed through Pins 87a to 30 in a N.C. situation. Most relays have a better than 100,000 operation cycles MTBF rating. I might agree with you if you were adding an Anti-Grind relay. That is a high current (+) signal and more critical to vehicle operation, but again proper components, soldered connections and quality insulation negates issues.Soldering is fun!

Great thanks. I have wiring diagrams but not sure exactly which wire or wire color I should be using. Can you advise? thank you.

Sorry, I don't have any info on your 2007 4Runner. Here is a photo from a 2014 Tundra : The wires are marked. Your connector might be different and your (-) Parking Light wire is Green instead of Tan. Anyway, here is the test. Using a Digital Multi Meter set to 20 Volts DC, connect the Red test lead to +12V constant and the Black Test lead to the suspect wire ( probably next to the Green (-) Parking Light wire ). With the switch in the OFF position, you will see 0V. When you set the switch to AUTO, the DMM should go to +12V. After this test finds the wire, the next test would be to cut the wire and see if the AutoHeadlight function still works. Finally, after all the testing, wire up your relay to the cut ends of the AutoHeadlight wire as shown above. Soldering is fun!

Awesome thank you again for such detailed explanations and a nice walkthrough of the procedure. I will check it out this weekend. In the meantime I did find a wiring diagram for my vehicle. I was wondering if I could cut the green/orange wire marked as "A" and accomplish the same thing??

It looks like that wiring diagram shows you some of the wires at the Headlight Switch. Bulldog Security says the Parking Lights are a (-) Green wire and that is confirmed by your diagram. Therefore the first wire I would test would be the Green/Orange wire you mentioned. You can see where it get a Chassis Ground output when set to Auto just like the Parking Lights output gets a (-) when in Parking Lights or Headlights position. Test with the DMM, then cut the cut and verify that AutoHedlights no longer works when the switch is in the AUTO position, then add in the relay.Soldering is fun!

ok now really confused. Tested the G-O wire at the combo switch using the method you outlined above. Did not get any voltage reading on any of the settings. Then found the G-O wire at the BCM and tested at that point. 12V with headlight switch off, 0V with parking, 0V with headlights and 12V on the "auto" setting. Then I simulated darkness by covering up the light sensor on the dash. All readings the same except that the "auto" setting was now reading 0V--expose the light sensor on the dash and it goes back to 12V. Again this is testing at the BCM. The only wire consistently reading 12V at the switch was the W-B wire. Any idea what is going on here or did I do something wrong?? thanks.

I don't think you would hurt anything if you cut that Green/Orange wire somewhere very accessible and did some live testing. With the engine running, set the Headlight switch to Auto. In normal daylight no headlights should be on. Cover the sensor and the headlights should come on. Now cut the Orange/Green wire and test again. With the wire cut the headlights should not come on. Soldering is fun!