Can you call someone to help you try to jump start the Jeep with jumper cables?
Try this: open the hood and try to prop the hood with a sturdy stick, etc. Then make a mixture of baking soda and water, and pour that on the battery cables and terminals. This will remove the corrosion. Make sure the cables are tight and tighten them if needed. Sometimes wiggling the cables will help make a temporary connection. Good luck, and let me know how it goes!
I've tried and now it doesn't seem to want to crank at all. I just get the clicking noise. Any other suggestions as to what the cause(s) could be? I understand that now, I may have no choice but to take it somewhere, but if I have advice first, I am less likely to get ripped off. I don't have money to throw around as if I am a member of the Rockefeller's. Thanks.
Well, my advice is that this does sound like a failed battery or a bad connection. The other thing it could be is a problem with the security system. Do you have a black or a gray key?
Ok, then we can rule out a security system issue. I think you will need to call a tow service and have them jump start the Jeep so you can then drive it to a shop or auto parts store, Sears, etc and have your battery and charging system tested. This should not be too expensive. Most auto parts stores or Sears will check this for free.
Hmmmm, an O2 sensor failing will not cause a no crank or no start problem on any vehicle. You could disconnect the O2 sensor and throw it away and the engine would still start and run. The only thing that maybe it could have been is if the O2 sensor shorted and blew a fuse, but this should have still allowed the engine to start, but the check engine light would come on. Why did the mechanic say that the O2 sensor was keeping the vehicle from cranking?