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Discussion Starter #1
For some reason, the display on my info center and radio seem to be really dim sometimes. I notice it more in the daytime, because in bright sunlight you almost can't even read them. I've noticed them getting fully bright again when I turn the key off to "accessory." I'm not sure what's causing this...I've tried fiddling with the dimmer switch, but it is turned up as far as it will go, and sometimes the displays DO display bright enough.

Anyone else experience this or know how to fix it?
 

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It sounds like you're describing the autolight function/ambient light sensor (the smoked dome on your dash). It is supposed to reduce dash/instrument illumination in low light situations, such as dusk and night time conditions.

Unfortunately, it doesn't work very well (as most GM techs admit). Mine used to come on a lot in late afternoon when the sun was actually still very high in the sky, rendering my instruments useless. It was incredibly irritating. A safety feature is not helpful if it prevents you from seeing your dash.

The easiest way to deal with it is to roll back your autolights and turn them off each time it does it. The permanent way to deal with it is to wire in a resistor and trick it into registering proper voltage.
 

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You might have a faulty sensor, but keep in mind that this sensor is light sensitive and has about a 60 second delay on it so it doesn't flicker every time something shadows it like a passing truck. For instance if you park your car in a garage and you drive out in full sun it will take a while for this circuit to realize "OK this was not a truck shadow" and come on, so display will be dim until this period expires. Also if it was dark when you last turned off your car and you start it up in full daylight next, it will take some time to adjust.
 

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Discussion Starter #5
I need to check where the dome is on the dash, but if that's the problem, my issue might be that I'm putting my hat on top of it when I leave work. I work at a restaurant, so I wear a hat, and I've always kept it on my dash in my other vehicle so I don't lose/forget it. Hilarious, if that's what's causing my issue!
 

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That would do it. Your car would think it's night and would dim the lighting.

Is this where you lay your hat?
 

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Here is GM's take on this
"#02-08-42-004A: Info - PRNDL Display Reduced Visibility for Approximately One Minute - (Mar 30, 2007)


Subject: PRNDL Display Reduced Visibility For Approximately One Minute


Models: 2010 and Prior Passenger Cars and Trucks (Including Saturn)


with Automatic Headlamp Control and Vacuum Fluorescent PRNDL Indicator Instrument Panel Cluster





After backing the vehicle out of a garage or dark environment into a daylight environment, the PRNDL display has reduced visibility for approximately one minute.

While the vehicle is parked in a dark environment, the sensor for the automatic headlamp/driving lamps senses that it is dark. When the key is turned to the run/start position, the automatic headlamp module will turn all driving lamps, the instrument panel cluster and PRNDL display ON in the nighttime mode. The nighttime mode intensity of the instrument panel lamps and PRNDL display is controlled by the automatic headlamp module and can be dimmed further by the customer using the dimming control of the headlamp switch.

When the customer then moves the vehicle from the dark environment into the bright sunlight, it will take approximately one minute before the headlamp control module recognizes this as true daylight and not just a bright overhead street lamp shining on the sensor. The headlamp control module will then turn the headlamps off and restore the instrument panel and PRNDL display to full brilliance.

Without the time delay, the automatic headlamp control module would switch to the night mode (turn on all driving lamps, instrument panel lamps and PRNDL display would dim) each time the vehicle was driven under an overpass or other darkened environment.

This is a normal condition and no repair should be attempted.

Ensure the instrument panel backlighting control is in the full bright position. This will help alleviate the condition.

You may demonstrate to the customer what happens by placing a repair order over the automatic headlamp control light sensor, which will cause the automatic headlamp control module to switch to the night mode in approximately one minute. All driving lamps will come ON, the instrument panel backlight will be dim, and the PRNDL display will also dim to the night setting in conjunction with the position of the headlamp switch dimming control. Demonstrate to the customer the variance in the instrument panel backlighting and PRNDL display while adjusting the headlamp switch dimming control to both ends of its allowable range. Advise the customer to keep the headlight switch dimming control in the highest position to allow viewing of the PRNDL display in a bright environment.



GM bulletins are intended for use by professional technicians, NOT a ""do-it-yourselfer"". They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.
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I can confirm this, as I drive under expressway bridges sometimes at day time, My head lights never come one (also controlled by the same sensor), its because of the delay, its not a "crappy engineering idea" to have a delay because imagine the results without the delay, every bridge you go under, even if it takes a few seconds to pass, it would eliminate your head lights and dim your interior lights, this would be rather annoying, wouldn't it?

Its a good idea and it works well.
 
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