Third Brake Light Problem - Need Help

[majjack]

The third (center) brake light on my 2011 Buick Lucerne stays on constantly, even when the car is not running. I do not know if the bulbs can be replaced or the unit itself is malfunctioning. I do not know how to access the unit so that I can disable it until I can determine how to resolve the problem. In the meantime, I have disconnected the battery so that the charge is not drained. Any advice will be greatly appreciated.

 

[MelsRegal]

Do the main brake lights work?

 

[majjack]

Yes. I reconnected the battery this morning and the third brake light was not on. It, as well as the main lights, now seem to be working the way they should. I'm thinking that water may have temporarily caused the problem. There were torrential rains here in NJ yesterday. The compartment under the back seat, however, was dry. I would welcome any suggestions. I'm going to keep my eye on the brake l light. The unit looks like it may be a strip of LED lamps. If anyone knows how to access it, please let me know. Then I would be better prepared to temporarily disable it if the problem arises again.

 

[MelsRegal]

Yes. I reconnected the battery this morning and the third brake light was not on. It, as well as the main lights, now seem to be working the way they should. I'm thinking that water may have temporarily caused the problem. There were torrential rains here in NJ yesterday. The compartment under the back seat, however, was dry. I would welcome any suggestions. I'm going to keep my eye on the brake l light. The unit looks like it may be a strip of LED lamps. If anyone knows how to access it, please let me know. Then I would be better prepared to temporarily disable it if the problem arises again.

Did you look in the trunk for the wire harness?

 

[HotZ28]

Yes. I reconnected the battery this morning and the third brake light was not on. It, as well as the main lights, now seem to be working the way they should. I'm thinking that water may have temporarily caused the problem. There were torrential rains here in NJ yesterday. The compartment under the back seat, however, was dry. I would welcome any suggestions. I'm going to keep my eye on the brake l light. The unit looks like it may be a strip of LED lamps. If anyone knows how to access it, please let me know. Then I would be better prepared to temporarily disable it if the problem arises again.

2011 Buick Lucerne CXL 4DR TRIM/BACK WINDOW SHELF

Diagram of OEM TRIM/BACK WINDOW SHELF. Contains 17 parts priced between $2.06 and $283.23. Fits 2011 Buick Lucerne CXL 4DR.

www.wholesalegmpartsonline.com

 

[majjack]

Thanks. I can see it clearly on the diagram. But how in hell do you get it out of there? It lie flat against the rear window.

 

[HotZ28]

The best approch is through the trunk.

 

[2007LucerneCXL]

You may want to check the brake pedal inside if it may be sagging slightly, while it should make all the rear brake lights illuminate, it may be something to check before getting deeper into the light removal.

To access the the light you will need to remove the rear shelf #4, the light and harness would be available. I replaced my rear speakers and this is how I remember unplug the light from a few years ago.

 

[majjack]

You may want to check the brake pedal inside if it may be sagging slightly, while it should make all the rear brake lights illuminate, it may be something to check before getting deeper into the light removal.

To access the the light you will need to remove the rear shelf #4, the light and harness would be available. I replaced my rear speakers and this is how I remember unplug the light from a few years ago.

View attachment 43434

You may want to check the brake pedal inside if it may be sagging slightly, while it should make all the rear brake lights illuminate, it may be something to check before getting deeper into the light removal.

To access the the light you will need to remove the rear shelf #4, the light and harness would be available. I replaced my rear speakers and this is how I remember unplug the light from a few years ago.

View attachment 43434

 

[majjack]

Thanks. I may not have to tackle it. The problem has not recurred over the last few days. If it does, I will probably take the car to a professional. I don't want to mess with it by pulling out its innards.

 

[WalmartTech21]

You may want to check the brake pedal inside if it may be sagging slightly, while it should make all the rear brake lights illuminate, it may be something to check before getting deeper into the light removal.

To access the the light you will need to remove the rear shelf #4, the light and harness would be available. I replaced my rear speakers and this is how I remember unplug the light from a few years ago.

View attachment 43434

if I remember correctly, the Parking Assist indicator (If Equipped) and the CHMSL share a harness which can be accessed without completely removing the parcel shelf. it should be right behind the seat back about halfway down on the passenger side. and according to GMPartsDirect, only the Titanium and Cashmere colors are available to purchase, you're SOL if you have an Ebony or Tuxedo Blue/Shale Interior or if the Harness if borked.