No interior lights!

mrmarkuSS

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Long Island NY
Buick Ownership
2003 LeSabre Limited
I discovered that I have no interior lights. The fusebox under the rear seat showed a blown 10 amp fuse; I replaced it,still no lights. I swapped the relay and still nothing. I don't think ALL the bulbs involved could be blown out. Where else to check?
 
By "interior lights", do you mean only the dome lights, or does that include the gauges, switches (on the door, steering wheel, and dash), radio, and HVAC illumination?
 
Interior lights and instrument lights are two separate fuses. I have instrument lights,which is why I said "interior"
Interior includes:
Foot well courtesy lamps
door courtesy lamps
rear compartment courtesy lamp
glove box lamp and switch
vanity mirror lamps
overhead console lamps
courtesy/ reading lamps

As I said,all dark. I don't think the dimmer is bad as the dash lights lower and with that said rules out bad door switches. Radio and HVAC lights are out,so I believe that falls under interior. The only door switches still illuminated are the door locks and passenger climate control.
 
See, that's why I asked what you meant.

Radio and HVAC are part of the dash illumination circuit, not interior lights like the dome and map lights. That means that the lights for those two items may be burned out, a wire broken, or some other issue.

I'd start with deciding which light of all that are dark is the easiest to remove the bulb, then test the socket for power at one of the two terminals. If you use a VOM or DVOM, you can use both probes and touch both terminals. You're looking for DC Volts, not Ohms.

You just might find that a number of bulbs are burned out. Of course, it could still be a fuse or two. Or a wire. Or loose socket contacts.

Or aliens! ( I'm putting on my foil hat now. 🤣 )
 
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That would be either the rear reading light or the glovebox. I have a multimeter and a test light.
 
Also be aware, if you are trying to test during the day, the light sensor in the center of the dash controls illumination of the interior lights. If it is sensing enough outside light or sunlight, it will not turn them on at all, regardless of whether you open a door or whatever else.
 
Also be aware, if you are trying to test during the day, the light sensor in the center of the dash controls illumination of the interior lights. If it is sensing enough outside light or sunlight, it will not turn them on at all, regardless of whether you open a door or whatever else.
I assume the light sensor controls the automatic headlights? If so,the sensor works fine. Even after sunset,still NO lights. So,it's a matter of power being supplied to the fuse,or the relay. That will be after I look at some bulbs.
 
The ambient light sensor for the headlights has one job: to decide when it needs to turn the headlights on. When they turn on, the dash lights are also energized. Their brightness is controlled by dimmer setting, which can be fully dark, fully bright, or anywhere in between.

That sensor does not affect the "interior" lights, so long as we all understand that "interior lights" are not the dash lights, but the dome and map lights. Also, the "dash lights" include the lighting for the radio HU, the HVAC HU, and any switches on the doors or steering wheel.

Both at night and in the daytime, when I unlock my door with the fob, the dome lights turn on, plus when I open the door, the dome lights turn on. Day or night makes no difference.
 
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The ambient light sensor for the headlights has one job: to decide when it needs to turn the headlights on. When they turn on, the dash lights are also energized. Their brightness is controlled by dimmer setting, which can be fully dark, fully bright, or anywhere in between.

That sensor does not affect the "interior" lights, so long as we all understand that "interior lights" are not the dash lights, but the dome and map lights.
Incorrect. I suggest you consult your owner’s manual (Pages 3-17 through 3-19 on 2005) or a shop manual wiring diagram. The interior lighting (dome lights, door lights, various courtesy lights) is controlled by the sensor in the center of the dash, as well as the exterior lighting including headlights:

Courtesy Lamps
If it is dark enough outside, when any door is opened, several lamps go on. They make it easy for you to enter and leave the vehicle. You can also turn these lamps on by sliding the INTERIOR lever all the way to HI.

Entry Lighting
If it is dark enough outside when you press the unlock button on the remote keyless entry transmitter, the interior courtesy lamps will turn on and stay on for about 40 seconds. The lamps can be turned off immediately by pressing the lock button on the remote keyless entry transmitter, turning the ignition key to RUN or activating the power door locks.

Delayed Entry Lighting
The interior lamps will turn on if you open the door when it is dark enough outside. When you close the door with the ignition off, the interior lamps will stay on for up to 25 seconds or until the ignition is turned to an on position. When the lamps turn off as a result of the 25 second timer or the ignition switch being turned on, the lighting will deactivate by way of the theater dimming effect. Locking the doors will override the delayed entry lighting feature and the lamps will turn off right away.

Theater Dimming
This feature allows for a three to five-second fade out of the courtesy lamps instead of immediate turn off.

Delayed Exit Lighting
If it is dark enough outside when you remove the key from the ignition, the interior lamps will turn on and stay on for about 25 seconds. This will give you time to find the door pull handle or lock switches. Once the key is inserted into the ignition, the exit lighting will be cancelled and the lighting will fade out. Perimeter Lighting If it is dark enough outside when the unlock button on the remote keyless entry transmitter is pressed, the DRL, parking lamps and back-up lamps will come on.

The phrase “If is dark enough outside,” is in there because all of this is controlled by the ambient light sensor. Driven Daily seems to have a one-off Lesabre in several respects, so not sure what is going on with that. I believe he has also said his washer bottle is on the driver’s side, which certainly makes it a one-off version or some kind of special factory custom.
 
Thank you for correcting the record jotzgr. My LeSabre has been off the road for over a year but I do remember that the interior lights would NOT come on in the daylight because by design they didn't need to.
 
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Incorrect. I suggest you consult your owner’s manual (Pages 3-17 through 3-19 on 2005) or a shop manual wiring diagram. The interior lighting (dome lights, door lights, various courtesy lights) is controlled by the sensor in the center of the dash, as well as the exterior lighting including headlights:

Courtesy Lamps
If it is dark enough outside, when any door is opened, several lamps go on. They make it easy for you to enter and leave the vehicle. You can also turn these lamps on by sliding the INTERIOR lever all the way to HI.

Entry Lighting
If it is dark enough outside when you press the unlock button on the remote keyless entry transmitter, the interior courtesy lamps will turn on and stay on for about 40 seconds. The lamps can be turned off immediately by pressing the lock button on the remote keyless entry transmitter, turning the ignition key to RUN or activating the power door locks.

Delayed Entry Lighting
The interior lamps will turn on if you open the door when it is dark enough outside. When you close the door with the ignition off, the interior lamps will stay on for up to 25 seconds or until the ignition is turned to an on position. When the lamps turn off as a result of the 25 second timer or the ignition switch being turned on, the lighting will deactivate by way of the theater dimming effect. Locking the doors will override the delayed entry lighting feature and the lamps will turn off right away.

Theater Dimming
This feature allows for a three to five-second fade out of the courtesy lamps instead of immediate turn off.

Delayed Exit Lighting
If it is dark enough outside when you remove the key from the ignition, the interior lamps will turn on and stay on for about 25 seconds. This will give you time to find the door pull handle or lock switches. Once the key is inserted into the ignition, the exit lighting will be cancelled and the lighting will fade out. Perimeter Lighting If it is dark enough outside when the unlock button on the remote keyless entry transmitter is pressed, the DRL, parking lamps and back-up lamps will come on.

The phrase “If is dark enough outside,” is in there because all of this is controlled by the ambient light sensor. Driven Daily seems to have a one-off Lesabre in several respects, so not sure what is going on with that. I believe he has also said his washer bottle is on the driver’s side, which certainly makes it a one-off version or some kind of special factory custom.

I try to be accurate when I post. Seeing your first post, it did not seem like my 2005 Limited behaved that way since I don't recall it ever doing that.

With this quoted post, I took the time to go out to my car while the sun is shining brightly on the car. Guess what? I was wrong. I apologize for the inaccurate data, plus I thank you for not being too terribly brutal when refuting it. I stand corrected.

Next, I need to double-check how my DRLs work. It's reported that they use the high beams on low power, but mine does not seem to do that. I will check them when I have time since now I'm not certain that I am so certain about them.

My washer bottle is on the passenger's side, though, just like everyone else's. So there's that going for it not being a unicorn, eh?

Again, my apologies to all.
 
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Has it moved since this post? LOL.
Nope. It's on the passenger's side.

I don't know why I said it was on the driver's side, unless I was thinking about my Malibu or my Xterra. But since that was 3 months ago, I don't recall what I was thinking.

I'll admit it is incorrect.

Check out all my other posts. If/When you find something else, let me know so I can correct any inaccuracies. It seems like that ought to be fairly easy.

I checked out that post so I could add an edit, but the Edit link is no longer there. If it's really that important, click the Report link so the Admins can correct it.
 
My daughter has been using the car,until she bought a newer one. I finally got around to checking this out more. Today I went outside and checked it out. Fuse #27, which I replaced when I started this post, was still intact. I decided to start with the front seat overhead lights and garage door opener. I replaced both bulbs and reconnected it; still no lights. The garage door opener had power,so after using a test light on the gray and the blue wires (the light didn't come on) I tried using a temporary bypass, tapping the orange wire (GM "always on" color) and splicing it into the gray wire. No light,but when I pressed the button,it turned on. Ok,so finally I got light. The passenger light didn't come on when I pressed the button. I turned the ignition key to run, and tried the light. Not working. I checked fuse 27 and it was blown. I disassembled my bypass wire,and replaced fuse 27. No blow,no lights,but garage door opener still lit with button pressed.

That being said,I traced some of the wiring in the back from the fuse panel,the wiring is protected by plastic channels and plastic tubing. Somewhere,that wire is chafed and grounding out somehow, even though the fuse I replaced months ago didn't blow, or it's something else. Maybe I should unplug or somehow disconnect the lighted sunvisors, the rear reading lamps,the floor lights until I just have the front map lights and see if that changes anything.
 
UPDATE: I started pulling some fuses and checking them, and even replacing #27 with a 10A fuse. Nothing. So, I put everything back together and went inside. Later, when I went to go get dinner, I pressed the unlock button on the remote...and I see lights come on INSIDE the car! I open the door, and sure enough, THE LIGHTS WORK! I started checking the ones I could observe-door courtesy lamps, rear seat lights/coat hook lights, driver side map light...,no passenger side (I had removed the burnt out bulb but no spare), no glove box light, no front seat floor light, no driver visor light, but the passenger visor lights work. I don't know what I did, but it works.
NOW THE BAD NEWS...The trunk will not pop open with the driver door button or the keyfob. The manual shows only the relay in the fusebox, but no fuse to power one side of the relay. IDK if its getting any power at all, And I replaced the electric trunk popper months ago and it worked. Also,the HomeLink three button transmitter isn't getting power either. I suspect the trunk relay feeds power to it as well, but I don't know what fuse powers it, and in another repair website it mentions because of the remote popper, it works by sending a signal from the driver door button to the driiver power window switch which then sends a signal to the driver door module which then activates the trunk relay. The relay under the seat does not have slots big enough to check if there's power going to it. Any suggestions?
 
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