Lamp Monitor - how does it work?

[Mag00]

Simple question, how does the lamp monitor work?

its probably one of my favorite things in my buick (95 PA)

thanks

[HotZ28]

This system will let you know when certain exterior light bulbs fail to light. You should have a display with eight LED’s indicating bulb status. When you first start the car, all eight indicators (LED’s) will light for a few seconds to indicate monitor system is working and then the lights will go out. When a bulb fails, an indicator will flash for a few seconds and then stay on until the failed bulb is replaced. (The bulbs are monitored, only when being used).

The bulbs that are monitored include; both headlight high beams, both headlight low beams, front & rear left turn signals, front & rear right turn signals, parking lamps including four tail lamps, right & left side markers, stop lights, including four rear & rear “high mount” and finally the back–up lights.

The “Adaptive Light Monitor Control Module” is located under the driver’s side dash and usually above the steering column. It has a large heat sink on the front of the module.

BTW, you can Click Here & go to "FIG 56" for a wiring diagram.

[Mag00]

Right, but how does it know the bulb is out?

[HotZ28]

The bulb gets its power through the ALD control module. If the power circuit cannot be completed through the bulb, the module lights the LED in the display.

[Blue Bowtie]

... but how does it know the bulb is out?

Basically, there is a high resistance B+ source applied to each monitored lamp circuit. A lower resistance (completed lamp circuit) acts as a pull-down, referenced to the B+. The load in the circuit drops teh reference voltage and prevents the logic from lighting the indicator LED. This occurs only IF there is a complete circuit through the lamp filament. An open circuit for any reason will not pull down the reference voltage, and that voltage at the limited current (high resistance reference source) will light the LED. It's really a rather simple design.

You could also get out, walk around your vehicle once a week while it was warming up (something many people don't do any more), make sure the lamps are working and lenses are intact, tires are inflated and not wearing oddly, all panels are intact, gas cap is on, the exhaust is not hanging, license plates are still there, etcetera. That's the way it USED TO be done, before the advent of automatic wipers (in case you didn't know it was raining), brakes for dummies, automatic headlights (for those who can't tell when it's dark outside), automatic dimming mirrors (see above), automatic climate controls, self-parking cars, and automatic snot-wipers. Then again, people used to be more responsible. Lexus has maybe finally dumbed us all down to their level.

[Mag00]

Originally Posted by Blue Bowtie

Basically, there is a high resistance B+ source applied to each monitored lamp circuit. A lower resistance (completed lamp circuit) acts as a pull-down, referenced to the B+. The load in the circuit drops teh reference voltage and prevents the logic from lighting the indicator LED. This occurs only IF there is a complete circuit through the lamp filament. An open circuit for any reason will not pull down the reference voltage, and that voltage at the limited current (high resistance reference source) will light the LED. It's really a rather simple design.

You could also get out, walk around your vehicle once a week while it was warming up (something many people don't do any more), make sure the lamps are working and lenses are intact, tires are inflated and not wearing oddly, all panels are intact, gas cap is on, the exhaust is not hanging, license plates are still there, etcetera. That's the way it USED TO be done, before the advent of automatic wipers (in case you didn't know it was raining), brakes for dummies, automatic headlights (for those who can't tell when it's dark outside), automatic dimming mirrors (see above), automatic climate controls, self-parking cars, and automatic snot-wipers. Then again, people used to be more responsible. Lexus has maybe finally dumbed us all down to their level.

thats a long explanation, most of which I dont really understand

Originally Posted by HotZ28

The bulb gets its power through the ALD control module. If the power circuit cannot be completed through the bulb, the module lights the LED in the display.

that was more succinct... but thank you

however, I do agree with you on the other stuff.
I dont use my automatic headlights (I like to put them on myself, thank you very much, hah) - also they would go on when under a bridge for a short amount of time, and thats annoying.

[TopherS]

Originally Posted by Blue Bowtie

You could also get out, walk around your vehicle once a week while it was warming up (something many people don't do any more), make sure the lamps are working and lenses are intact, tires are inflated and not wearing oddly, all panels are intact, gas cap is on, the exhaust is not hanging, license plates are still there, etcetera. That's the way it USED TO be done, before the advent of automatic wipers (in case you didn't know it was raining), brakes for dummies, automatic headlights (for those who can't tell when it's dark outside), automatic dimming mirrors (see above), automatic climate controls, self-parking cars, and automatic snot-wipers. Then again, people used to be more responsible. Lexus has maybe finally dumbed us all down to their level.

I prefer not to think of utilizing the technology that has been incorporated into our cars as being "dumbed down". I have automatic wipers, headlights, dimming mirrors and climate control, plus memory seats and mirror settings, rear parking sensors...among other things, and take advantage of every one of those options. I let my car take care of certain things and it's kind of nice knowing I don't have to take my mind off of the road, even for that millisecond that it takes to reach over and turn on the wipers. Yet, I still walk around the car to check my lights, I check my tires (even with the car's tire pressure monitor), I turn on my (automatic) headlights when the situation warrants it, because that is the responsiblie thing to do. I don't believe that we are dumbed down by the advances in technology...I'm pretty sure that there were irresponsible people back in the day who did not turn on their lights when they should have, or checked their tires or lights, etc., just as there are irresponsible people who don't do that stuff now.

Frankly, I remember when people used to talk about cars in the future that would drive themselves, practically fly us to where we wanted to go. I remember wondering what our cars would do for us. As technology grows, many embrace it...whether it be in letting our cars do some of the tasks that we used to do...or whether it be improving our electronic systems in our homes. Many don't embrace such advances. They like to do things their own way. I respect that many people would rather do it themselves. My 87 year old grandfather refuses to drive an automatic because he believes that the car should "shift gears when HE wants it to and not when some a$$hole in Detroit wants it to" (his words). It's just the way that he wants it... and that's cool.

The level of technology within our cars does not make us dumb...it's the amount of responsibility that we take that speaks to our intelligence.

Just my