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Automatic Headlight Sensor

liteft01

SM 2007
SM 2006
Full Member
Joined
Aug 18, 2004
Messages
460
Location
Shawnee Kansas
Can this sensor be calibrated.  I was driving around the other evening, thinking my headlights should be coming on.  I even saw other AV's on both sides of the highway with their headlights on, but mine weren't.  They finally came on, when I entered my garage.

I asked a service rep at my dealership, at first he wasn't sure and then, in the next sentence, said no it had to be replaced.  After this place tried selling me wbh running boards for my cladded Av, I'm not sure I totally trust them.
 
The short answer is no. They were right this time it would have to be replaced.

The sensor monitors light as you are aware and as light levels go up or down it becomes more or less like a resistor. This causes the voltage on a circuit to fluctuate. Once the voltage hits a certain point the computer triggers the lights to either come on or off. Now if it is possible to adjust something somewhere it may be possible to adjust what voltage the computer looks for before turning on or off the lights. IF that is possible that would be something in the programming of the computer that only a Tech-II could do. And since pretty much the only people with Tech-IIs are the dealers then you would have to go there. Even if it isn't a direct programming option in the Tech-II it is possible that the latest software update may correct this. Again this is pretty rare but possible if there were enough complaints about when the lights were comming on. To give you an idea of how much this stuff controls, in the 03 many of us complained about how bright the high beam indicator light is on the dash. Enough people complained that they addressed this concern in a software update. I haven't done this yet but if I go in and have them re flash the computer in my truck it will dim that indicator light. If you are out of warranty you will be charged for this service. That is why I haven't done it yet. I would ask the dealer or if you don't trust them 100% call another dealer and ask again if the Tech-II can adjust this setting or if there is a software update that maybe corrects this.

The least expensive fix is to just put a map or something over the sensor and your lights will be on all the time.
 
It's an 06 and still in warranty......but with all the strange things my husband keeps, for some use someday,  I bet I could find something small enough to place over it when needed.  Or I could just turn them on with the switch!  Thanks for the response though.  My next warranty issue I have it in for, I'll have them check into it.
 
liteft01 said:
It's an 06 and still in warranty......but with all the strange things my husband keeps, for some use someday,  I bet I could find something small enough to place over it when needed.  Or I could just turn them on with the switch!  Thanks for the response though.  My next warranty issue I have it in for, I'll have them check into it.

Yeah if in warranty then have it replaced. Also when you go in ask them about updates to the programming. I don't know that there is anything for an 06 but while underwarranty I would ask. Like I said I know there is an update for mine but I haven't taken it in because I don't really have the time and I rarely use high beams so the issue doesn't really bother me all that often.
 
Technically you can't calibrate.

However, on my '02, I believe it is a simple photoresistor.  So, if you can figure out the resistance that trips the headlights, you could technically adjust the effective resistance of the photoresistor that provides the daylight sensing.

SInce you'd like to make the headlamps turn on when it is lighter than the photoresistor expects, you could wire a potentiometer in series and dial up a "lighter" trip point.

If you wanted it to come on when it's darker, however, you'd have to wire a potentiometer in parallel.  The utmost control would be to wire one in series and one in parallel.

Mine seems to do the opposite.  It cycles on and off in brighter conditions than I'd prefer.
 
liteft01 said:
Can this sensor be calibrated.? I was driving around the other evening, thinking my headlights should be coming on.? I even saw other AV's on both sides of the highway with their headlights on, but mine weren't.? They finally came on, when I entered my garage.

I asked a service rep at my dealership, at first he wasn't sure and then, in the next sentence, said no it had to be replaced.? After this place tried selling me wbh running boards for my cladded Av, I'm not sure I totally trust them.

Same thing happened to me a couple of nights ago.  Was driving, thought they should be on, and saw other AVs with their lights on.  Looked at the switch, and the green light was not on.  Turn the lights on manually and cut them off, and the green light came on.  Then they came on by themselves.
 
I just noticed my lights stay on all the time with the switch set on auto (no green light). 03 not under warranty any ideas?
 
lminor204 said:
I just noticed my lights stay on all the time with the switch set on auto (no green light). 03 not under warranty any ideas?

Change the sensor I think the sensor is about 25 bucks
 
So do we know for sure this sensor is a resistance based sensor? I would like to disable mine so my lights come on all of the time which would be simple if it is indeed a resistance.

Thanks!

Rodney
 
shane67lchs I don't have a part number because they are always changing but do search Sunload sensor.


Rodney do a google search "Disable Automatic Headlights" lots of info about it.
 
Thanks... The ones I have seen so far turn off the headlight detection. I want them on all of the time.

Rodney
 
I wish they would turn on if wipers are on for more than 5 seconds, then stay on til the wipers are off and photosensor sees enough light...
 
In the 03 up it's also a sunload sensor for the HVAC so it will effect how the AC works. But if you want the lights on all the time cover it.

marzahld I'm not sure how you could do that.
 
MS03 2500 said:
In the 03 up it's also a sunload sensor for the HVAC so it will effect how the AC works. But if you want the lights on all the time cover it.

marzahld I'm not sure how you could do that.

Cover it with a black screw on bottle cap  with a wad of tape on the inside......you can even be creative and play with different colorcaps  and even drill small holes in the cap to "calibrate" it until the lights go on to your liking..also kicks on the remote entry/puddle lamp lights in the daytime for the timeout period.........remove it and no trace you ever screwed with it.
 
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