i have a 1990 jeep cherokee... i dunno about the back lights, but the window thing could be something to do with the motors for the windows, or the electrical signals getting to the window motors. my left rear side window has spells where it won't roll down for no particular reason.
also, if you need service, try and find a mechanic (NOT a jeep dealership) that has worked on jeeps and knows about them- they're REALLY quirky cars and you don't want to pay a lot of money to "fix" something that wasn't broken in the first place. for example, my car sometimes won't start when i turn the key- like, nothing happens, no turnover, no nothing. it's just because the gearshift is really sensitive about registering when my car is in park- all i have to do is push the gearshift forward with my right hand while turning the key with my left- car starts! also, i had a problem about a year ago where my car wouldn't turn over- it'd chug and chug but never actually crank- turns out there's a crank sensor that sends an electrical current from the flywheel to the alternator, and when it gets corroded the signal doesn't get through. it's a really easy sensor to get to- it's like, right on top of everything when you open the hood, and all you have to do is unplug it and plug it back in about twenty times to clean off the male/female parts.
good luck with your wonderful new car! Jeeps are AWESOME! if you take care of it, it will last a LONG time!
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She answers hard acrostics, has a pretty taste for paradox
She quotes in elegiacs all the crimes of Heliogabalus
In conics she can floor peculiarities parabolous
-C'hi