If it is the tail lights that are inop there are some common problems associated with this model Jeep. The most common is the tail light sockets. They often melt the housing they fit into and consequently lose ground. '''The only way to properly fix this is by replacing the entire taillight assembly'''''italic text''. They have come way down in price and I'm sure by now there are aftermarket solutions. I usually don't use aftermarket electrical parts, but Dorman has made some good stuff and proved me wrong. The very first thing I would check is that the instrument cluster lights are working when the lights are on. If not, check the fuse-they are on the same circuit. It could be that simple. Keep your eye on the cluster lights-when they're not working,neither are your tail lights!
If you have the fancy "Automatic " lighting system it can get a little weird. There was a big problem with BCM's (Body Control Modules). When they go bye-bye, you might think that your Jeep is possessed! The lights will flash on and off in the middle of the night! Unfortunately you will need some specialized equipment for this. The BCM isn't that big of a deal, but you will need a DRBIII factory scan tool to "marry" the BCM to the Jeep.
If I had to make a wager, it'd be the sockets and tail light assemblies. It's a very easy repair-pop the hatch and remove a couple of screws. The assemblies used to come with brand new sockets and bulbs. Plug n play!Love me some Jeeps!
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Carefully look at the socket for the rear tailights and all lights on that circuit. You may be getting a poor ground or corrossion is causing a ground feedback. Hard to diagnose something like this from afar even with 10+ years of factory training on Jeeps. Does anything change if you have the brake lights on? This is a ZJ model right? If its a Grand Cherokee that changes everything except looking at the light sockets and associated wiring. Does your Jeep have a trailering plug? That can also create some havoc. If you want to give me the VIN number I'll dig deeper. If there's a way to privately message on here I'll give you my phone number and help as much as I can.
If it is the tail lights that are inop there are some common problems associated with this model Jeep. The most common is the tail light sockets. They often melt the housing they fit into and consequently lose ground. '''The only way to properly fix this is by replacing the entire taillight assembly'''''italic text''. They have come way down in price and I'm sure by now there are aftermarket solutions. I usually don't use aftermarket electrical parts, but Dorman has made some good stuff and proved me wrong. The very first thing I would check is that the instrument cluster lights are working when the lights are on. If not, check the fuse-they are on the same circuit. It could be that simple. Keep your eye on the cluster lights-when they're not working,neither are your tail lights!
If you have the fancy "Automatic " lighting system it can get a little weird. There was a big problem with BCM's (Body Control Modules). When they go bye-bye, you might think that your Jeep is possessed! The lights will flash on and off in the middle of the night! Unfortunately you will need some specialized equipment for this. The BCM isn't that big of a deal, but you will need a DRBIII factory scan tool to "marry" the BCM to the Jeep.
If I had to make a wager, it'd be the sockets and tail light assemblies. It's a very easy repair-pop the hatch and remove a couple of screws. The assemblies used to come with brand new sockets and bulbs. Plug n play!Love me some Jeeps!