• Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

Coolant guage on the fritz...

F

freewithfire

NAXJA Forum User
Location
orlando fl
I've got a coolant temperature guage that doesn't like me one bit. It quit working a while ago and it really didn't bother me that much. I've finally decided to do something about it, and now I can't seem to get anywhere. I just replaced the coolant temp sensor, and I still have no improvement...the guage rests at the bottom...any suggestions from the peanut gallery?
 
The gallery suggests that you post the year of the XJ. Activating crystal ball.........91 ?

Have you measured the resistance on the sender? It should be less than 1000 Ohms when warm.

Try shorting the connections to the sender to see if the guage budges.
 
Last edited:
Clarification....

There are 2 collant temp senders. One for the guage, and one for the ???.

The one closest to the firewall is for the guage (or indicator -- light).

I'm not sure about this, but there may actually be two different types of senders -- one for guages, and one for a simple warning light. You might need to confirm you were given the correct type.
 
well, u say it rests on the bottom...

so im assuming it has no power going to it then
if it was grounded/shorted out it would be pinned in the other direction

so its either-
loose/poor connection
or
not getting power
or
bad gauge


try grounding it out to see if it pins out, that will tell you (most likely) if the gauge works or not
 
If I'm correct that you have a 91 XJ, your temp gauge should peg when the sensor is disconnected and drop to zero when it or its wiring is shorted. The temp and oil pressure senders are the reverse of the previous years. Thus, if it is at zero, I would first pull the plug on the sender and if it does not peg the gauge, look for a short in the wiring or a defective gauge. If it does peg the gauge when disconnected, the problem is in the sender.

Oh, forgot to mention, I believe if you have the 91-up idiot light sender instead of the gauge sender, it will stay at zero until it overheats. Make sure you have the right sender.
 
freewithfire said:
When I turn the key, the guage jumps to the opposing side, until the Jeep starts, then it drops again. Doesn't that mean it's getting power?
Click to expand...
Yep. That's actually a good sign.

The IGN switch grounds the wire going to the guage when it's in the start position.

Try disconnecting the VT/YL wire from the sender, and grounding it while observing the guage.

It's either going to be a bad connection or a bad sender.
 
I don't think it's a bad sender, because I just replaced it, and it would do the same thing with the old one (jump to the other side of the guage when I start it, that is). So what do I do if it's a "bad connection" and are we still talking about the sender at the front of the engine?
 
Did you get the correct sender? There are two different types: one for the light and one for the gauge.

They both go in the same spot, in the back of the engine near the fire wall on the drivers side, right next to the valve cover.
 
You must log in or register to reply here.

Similar threads

V
High temp woes
2
Replies
21
Views
399
Vitzaa
V
M
Coolant Temp Sensor
Replies
3
Views
2K
Unclewolverine
U
G
Coolant System No Pressure
Replies
9
Views
2K
Woodswanderer
W
I
High idle, smells like gas, running out of things to replace
Replies
2
Views
2K
Inverhyt
I
O
2000 XJ Failed Colorado Emissions high CO
2
Replies
27
Views
2K
Ken M
K
Back
Top