Is there an adjustment via the truck's ECM (of elsewhere) to adjust the sensitivity of the twilight sensor that turns the headlight and dash lights on/off? Mine turns off the lights too soon/late, and I am unable to see my cluster :eek: ,
instrument cluster that is.

Thanks,

GREAT Question.


I was going to ask the same thing but kept forgetting.

I would like mine to come on sooner and go off later than it is.

I will on occasion throw a glove over the sensor to get them to come on.

You know its just too much trouble to turn the knob ):h

Is there and adjustment to this?????

i have the opposite problem mine come on to early and wait to long to go off. is there a way to adjust it

Just be happy you don't live in Canada and have no way of turning the head lights off on the 04/05 trucks. My 02 turns the light out when I place the parking break on, the 04 turn the key on in the dark and the lights go on. There is no way to turn them off with the key in the run position, thats with or without the parking break on.

the switch will have a dark circle. turn it down towards it and it shall spring back up but the headlights will be off.

as far as those that don't come on in time, if you have fog lights, just turn them on and the dash will illuminate with it. that is the only wany i have found around those issues.

the switch will have a dark circle. turn it down towards it and it shall spring back up but the headlights will be off.
His won't do that because he has canadian pcm programming. They made the law in canada that you can't turn lights off when it's dark out, period. Sounds Censored to me.. I have a buddy that has a truck originally from canada and his is like that too, never got reflashed with the correct stuff when they changed it from kmh to mph.

Personally my lights come on slightly sooner than I like.. Could always bypass the sensor entirely but since it's so easy to flip it off I haven't bothered.

Now i know why that switch dosent work:o:
Thanx!

Yea, that's what I've been doing, turning the fog lights on. I've been thinking of some kinda "filter" to place over the sensor. Any ideas??

thanks for the update. i guess you can thank the canadien gov't for that. there has to be a way to program the sensitivity.

Mine don't come on soon enough and, like some others, I either turn on the fog lights or throw something up on the dash to cover the sensor. My Service Manager has told me there is no adjustment like there used to be on some of GM's cars. I hope someone can prove him wrong. It is a nuisance!

I wonder if some are more sensitive than others. If they were different then some of use might trade... Not sure how to see if they are different, maybe an ohm meter?

I have a headlight modulator on my ST1100 motorcycle. The modulator has an "IR" sensor very similar to the twilight sensor. I wanted to be able to turn the modulator ON and OFF manually. I called the manufacturer and got info on how it works. He told me the IR sensor sees a change in resistance in the presence of sunlight. When the change is detected, the sensor turns ON or OFF. What I did was cut the 2 wires about 5 inches back from the IR sensor and connect a mulimeter. Got the resistance with no light and then got the resistance with light present - has to be IR light, like from sunlight or flashlight - florecent garage lights won't do it. I found the difference in resistance was 100-Ohms. I went to Radio Shack and bought some small 1/4 Watt 100-Ohm resistors and installed one in the wire coming into the sensor. Then on the wire going out of the sensor I installed an on-off or toggle (whatever) switch allowing me to turn it ON or OFF when I want.

Now, with that said it seems the twilight sensor works opposite of the headlight modulator sensor on my bike. On the bike, the modulator turns ON when light is detected. The truck twilight sensor seems to turn ON (ie headlights ON) when light is absent. Different results, but I am sure it works the same way. It would take some time and experimenting with different resistors, but you could probably install one with lower or higher resitance to get the lights to come on sooner or later - OR you could install a potentiometer inline with the sensor and mount on the dash somewhere like beside the Passenger Airbag switch and adjust it manually, on the fly.

I'd like to disable mine all together and turn the lights on and off manually, but don't feel like messing with it at this point. Maybe when I install backup lights I will.

Mine is pretty good most of the time but if I'm pulling the trailer, I like the running lights on earlier. I just use the switch to force them on.

you can always brighten the dash lights with the knob if the lights are on too early.