97 Jeep GC coolant sensor bad

I have a 97 Jeep Grand Cherokee that intermitantly shows "COOLANT SENSOR BAD" on the display panel. I have replacet the "coolant level sensor" in the recovery tank and the "temperature sensor" in the thermostat housing but that did not fix the problem.

What causes the "COOLANT SENSOR BAD" message on the display panel?

What is the resistance of the coolant level sensor when the coolant level is correct?

What should I look for next?

Hi!

Looking around various Jeep sources I find that this is a rel. common problem.

I have not found any solution to it, it could be faulty wiring, but I wonder...

I have also tried replacing the level sensor, but still the same intermittent problem.

I have noticed that when rel. cold outside temp (let say less than 10degr Centigrade) it does not appear.

The resistance of the sensor should be 2.3kOhms, and I have tried to replace the sensor with a pure resistor, still the same problem. The "Bad" message appears when the sensor is disconnected, or maybe when the current through it is too low.

I tend to think that there is a problem with the computer making the current through the sensor fall below the threshold under certain conditions. Maybe there is another sensor or device on the same cirquit that sometimes short cirquits or drain the amps from it.

If you find a solution let me know!

Regards,

Joakim

I've had the same stinking problem. I bought a jeep with 100,000 on it and within 50 miles from the place that I bought it, the COOLANT SENSOR BAD display shows up. I too looked it up on the internet to see what the problem was, replaced it only to find that less than a Day later it said it AGAIN! I was a little miffed, because the dealerships don't generally take back electric parts after they've been installed (or dipped in Antifreeze).

So I was curious, does COOLANT SENSOR BAD, mean that I've got low coolant? So I took the reservoir Coolant Sensor out and let it hang to find that I got the message, "COOLANT LOW". So I put it back in and I've never seen the warning light again! Weird! That's been about 3 months! Needless to say, if it comes up again I'll be hacked :).

Hope it works for you.
Ryan

I had the same problem, it turned out to be a loose battery cable (-).

I have fixed it finally!
Oxidation on the connector between the VIC (the computer/display) and the cable to the sensors. Just to take down the panels, and clean, and finally silence!

I have fixed it finally!
Oxidation on the connector between the VIC (the computer/display) and the cable to the sensors. Just to take down the panels, and clean, and finally silence!
Just take down what panels? Also, where on the engine is the coolant sensor located? Thanks.

Hi Dude!
The coolant level sensor is located on the coolant fluid tank in the engineroom (behind the battery)

The panels - I mean the lower half of the dash board start from the passenger door, unscrew the right section, and the section around the VIC (the display). There is a clip between the mid section (VIC) and the left one (driver seat), which you can unhook.
Then unscrew the VIC, and work on the connector, perhaps spray some CRC 5-56 on it (I didnt)!

Regards, joko

Hi Dude!
The coolant level sensor is located on the coolant fluid tank in the engineroom (behind the battery)

The panels - I mean the lower half of the dash board start from the passenger door, unscrew the right section, and the section around the VIC (the display). There is a clip between the mid section (VIC) and the left one (driver seat), which you can unhook.
Then unscrew the VIC, and work on the connector, perhaps spray some CRC 5-56 on it (I didnt)!

Regards, joko


I have the same warning 'coolant sensor bad' I changed both the level sensor in the coolant tank and the coolant temperature sensor located next to the radiator hose going to the radiator, 5.2 v-8. I still get the alarm. I'll will now check the connections at the vic display, thanks
edclarke

I have the same warning 'coolant sensor bad' I changed both the level sensor in the coolant tank and the coolant temperature sensor located next to the radiator hose going to the radiator, 5.2 v-8. I still get the alarm. I'll will now check the connections at the vic display, thanks
edclarke

Did checking and/or cleaning the VIC connections get the alarm to go off? Is anyone having trouble with there Grand Cherokee starting up on the first try with a cold start? My GC is only starting on the second or third try after the coolant sensor alarm started going off. Thanks again.

I have a 94 JGC V8.. I was having the same problem.. Today I went to a dealer and bought the coolant lelvel sensor (the one in the coolant bottle) for $20 and replaced it immediately... It looks like it worked...
Good luck to you all there..

does it always say "coolant level low" if the sensor is bad?

My GC says " coolant sensor bad" .. I mean said :)

"cooland sensor bad"


I recently got a 97 GC and now I don;t feel so alone....

looks like I have some replacing and cleaning to do !


YEEE HHAAAWWWWW

"cooland sensor bad"


I recently got a 97 GC and now I don;t feel so alone....

looks like I have some replacing and cleaning to do !


YEEE HHAAAWWWWW

I had dash apart(real easy) removed auto a/c climate control unit and you can see wire harness to VIC unit. I wiggled the wires and now the beeping is gone. finally after changing all other obvious solutions, a simple wiggle worked.

Check the coolant and extra coolant

Most modern cars have a translucent plastic overflow tank that holds extra coolant, and it is attached to the radiator with a hose or tube. Simply check to see that the level is up to the mark. If you need to add coolant, use a mixture of half water and half antifreeze. If you don’t have an overflow tank, you’ll need to remove the radiator cap itself. The coolant level should be within a couple of inches of the top.Don’t remove the cap from a hot radiator. Wait at least 20 minutes for the engine to cool down, and always cover the cap with a rag as you remove it, to avoid hot water coming into contact with your skin.

The problem Has nothing to do with the coolant sensor, Or for that matter anything to do with the cooling system at all, Check out this thread (http://www.jeepforum.com/forum/f13/coolant-sensor-bad-finally-fixed-175207/). You will see that it actually has to do with crummy soldering on the back of the VIC (Vehicle Information Centre), & all that is needed to fix this problem is a bit of solder & some patience, I know this because I have changed my coolant sensor on the engine block and in the reservoir & the thermostat just to be sure & all with brand new original jeep parts not aftermarket rubbish, & all it took was a bit of solder.

I have two links to show that the sensor referred to in the VIC as being bad is only the switch in the coolant overflow tank and has nothing to do with any of the other coolant sensors in the engine.
Look at these links to verify this:

http://autorepair.about.com/od/lightsbuzzers/ss/How-To-Test-Your-Cherokee-Coolant-Sensor-And-Wiring.htm#step2

http://autorepair.about.com/od/lightsbuzzers/ss/How-To-Test-Your-Cherokee-Coolant-Sensor-And-Wiring.

This first one shows what you need to know. I dont see any problem with trying to solve this by doing the soldering nor trying to clean contacts etc since the car is almost 20years old. But I want to tell Chrysler that they should be ashamed to label that fault in the VIC as being a coolant sensor when it was actually a switch and not a sensor. Could have saved a lot of us a lot of grief.

Ken