Bogus warnings on my Jeep's dash console?

[Timbo is here]

Cannot be a fuse - they either work when they are ok or when blown not work at all - no part working sometimes.

The coolant sensor is either wiring or a computer fault.
The battery light is down to whatever monitors the battery not getting a correct voltage signal so is most likely the wiring.
12 years of age is the real problem -time for a new car. They were not designed to last more than 10

 

[wren378]

I have a 1997 Jeep grand cherokee. For about 3 years it has been flashing "coolant sensor bad" on the console display. I have had every sensor the mechanics can think of replaced. And had to tested on several times of computers and it comes up with no codes. And now, All of the sudden two days ago, i started my car and the needle on the battery gadge went to 0 and the car started screaming "check battery". Now I just had my battery replaced last month and the car started right up. I stopped at a gas station. Turned the car off and it started right back up all the while the dash is telling me the battery is dead. Half the time I start up the car and it says the battery is dead, half the time it says the battery is fine for about 5 min. and then the needle falls and it says it's dead again. All my battery terminals are clean. Someone suggested it was a fuse going bad. Is there a battery charge monitor or coolant sensor monitor that would have a fuse that could be going bad??