philwarner

I just got my "new" 96 Grand Limited and am sorting out some things. Just before I took possession My brother-in-law said the "bad coolant sensor" and "low coolant" messages came up. The overflow bottle was nearly empty and the radiator was slightly low when I got it and filling both and contact cleaning the bottle level sensor connector got rid of the low coolant message but the bad coolant sensor message remains.

I've read the re-soldering of the display to eliminate a display fault, but first I want to check the sensor itself. Where the heck is it on a 5.2 V8? I can't find one looking from the top but did find a free 2-pin female connector on about 12 inches of wire coming out of the wire harness on the left side of the engine just behind the air cleaner box. Could this be a loose coolant sensor connector?

I've also gotten a "check battery" message twice while starting it in the drive even though the battery was just fully charged and tested good with a load tester; it reset the date/time display one of those times. I haven't yet removed the battery connections, but tightened them and they look clean.

And several times while idling it just stopped running. Could either of these things be related to the "bad coolant sensor" message or are they likely separate issues?

I also tried adjusting the emergency/parking brake at the equalizer link under the back, tightening the cable adjuster nut about an inch, but the E-brake still pulls all the way up with little resistance. Is it time for new rear brake shoes?

And finally (for now) is there any site like the Great Lakes XJ site that has downloadable Factory Service Manuals for Grand Cherokees? Are these what you folks call the ZJ models?

johnbanghart

the coolant level sensor is in the over flow box its that lil thing plugged in there the part is like 20.00 at advanced auto the coolant sensor is near were the top rad hose goes into the feed neck you should see a lil sensor in the top of the intake near the top hose....john

philwarner

Thanks, John,

I had cleaned the connector for the coolant level sensor and tried it connected and unconnected and the “coolant sensor bad” message persists. The coolant level sensor in the overflow tank measures open with with my VOM with the coolant level at the full mark on the bottle so I assume it is an open or closed switch? Does it just pry out of the plastic tank?

I think I found the temperature sensor you described on the right front side of the engine near the top radiator hose between the AC lines and the alternator, but it looks like it is in the air intake rather than the water jacket; Is this the coolant temp sensor? It measures 12.69 K ohms resistance at an ambient temp of 75 degrees.

pwb

http://www.justanswer.com/jeep/2j0en...gine-jeep.html

or

http://www.jeepforum.com/forum/f13/c...cation-575690/

johnbanghart

yes the coolant level sensor pulls right out it takes alil muscle so dont be shy ahahhaha
check out them links PWB posted there very helpful

philwarner

Thanks for those links, pwb; I'd never have found it without those pictures and even with them I thought at first my engine didn't have one. That little bugger is well hidden, but it appears to be connected OK.

Now if I could just figure out where the loose two pin connector with blue and green wires that comes out of the harness just behind the air filter is supposed to go.

philwarner

Thanks again, John. I got it pried out and cleaned it up and was able to measure 3.3K ohms across the pins with the float up; it looks like some sort of enclosed reed switch that is opened by a magnet on the float rod.

Reinstalled I had no message at first, but once I moved the Jeep I still get an intermittent "coolant sensor bad" message. Guess I need to try a 3.3K ohm resister across the connector to see if it is the sensor or the VIC.

I tried removing the cover under the driver's dash to clean the connector there as recommended in this JeepForum thread, http://www.jeepforum.com/forum/f13/c...-fixed-175207/, but couldn't figure how to "pop it off" without breaking something. Any idea how this cover pries off?

johnbanghart

i,m gonna almost bet its your vic, mine does the same thing i have replaced the coolant level sensor and the message was off for about a hour or so then came back on not a big deal it comes on from time to time not like every day.... from what ive heard sounds like the solder comes loose inside the vic and thats what actually causes this issue so if you ever get it out you might wanna take a soldering gun to all the solder joints and re set them this may help you and save you a few bucks

philwarner

Thanks, John, I drove the ZJ to our closest little town today to get oil and trans filters and some ATF+4, and there was no message on the way, then it popped up leaving the wife at the grocery, and then no message on the way home. I saved a writeup on removing and soldering the VIC, but I think I'll let it ride awhile now that I know it is a harmless annoyance. BTW, the ATF they had is called SynGard and is made in the USA by Cross Oil and is packaged at Smackover Arkansas. I also found some "Little Tree" air fresheners at the grocery in a Dark Rosewood color to match the Jeep and they were also made in the USA. Take That you inscrutible little bas_____s