Hello. My nieces wife (That's right you heard me) has a 2004 Grand Cherokee and the one rear brake light bulb seems to not want to work or only works sometimes. Bulb has been changed a few times and connection cleaned. The running light and back up lights seem to work but the brake light is the problem. Someone said this is a common problem for this specific year/model. Does anyone have any info or experience with this? Thanks in advance.

 

Look for melted plastic around the contacts inside the bulb holder. Heat will build up when the brake lights are on for extended times, like when sitting in traffic. You can swap a bulb holder with a reverse light to see if it makes a difference. All the bulbs are the same and the holders are also. The difference is in the circuitry supplying them.

The problem is not specific to that year/model, but to newer jeeps in general. I think they didn't use high temperature nylon when they made the holders.

 

There are little metal tabs around the edge of the bulb holder. Try sliding a very thin screwdriver or the edge of a thin knife blade under the tabs and lift them up, slightly. These are the connection points to the electricity that goes to the bulb. I have had this happen on the rear brake and signal turn lights. Both times I just lifted up on the metal tabs. They make contact again and everything was fine.