Why is the Low coolant light on in 96 grand Cherokee?

Answer 1

The light is on because the coolant level is low. The sensor is located inside the reservoir tank on the passenger side near the firewall. Fill the reservoir tank to the appropriate level ("HOT" or "COLD") with the proper 50/50 antifreeze mix. This should shut off the light. It may come on again after a short period of operation and cool down cycle if the level insided the engine is severely low.

I own the same vehicle and I always have a warning that my coolant sensor is bad. The following is not MY answer, it is something that I read while trying to figure out why my Jeep does all the quirky things that it does.

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The VIC (vehicle information center) has some issues with the solder connections between the display board, and the CPU board. They have a flexible connector between the boards, that is "wave soldered" at the factory. Due to some quality issues, units from 1996-1998 have some connections that didn't receive the full amount of solder required for reliable connection. Pin 14, which connects to a pink wire on the electrical harness is the culprit. Once that connection is secured, the false "Coolant Sensor Failure" will go away. That sounds very technical, but if you have even the most rudimentary soldering skills, you can fix it with a 30 minute investment of time, for free. Google "removing the VIC" for more detailed information about what panels must come off to get the unit out- it's a bit involved, as it requires removal of the dash storage compartment door. I won't cover that here... Once the unit is out, unscrew the 6 Torx screws holding the unit together. Once the screws are out, the unit can be split in half like a clamshell. In between the two circuit boards are a ribbon cable, with fairly stiff wires in it. The problem lies in the solder connections of the riibbon cable, to the boards. Under a magnifying glass, you may be able to see one or more "cold solder" joint connections. These look like a little silver mountain, but some may be missing some solder, or be a very dull color- not the bright shiney connection of it's neighbors. I chose to heat all of the connections one at a time, and add a tiny bit more solder to each. Once putting the unit back together, and re-installing, I haven't had any further issues. The only other alternative is to either ignore the message center, or purchase a VIC from some place like E-Bay, or a junkyard.