Hey guys, I have a 96 cherokee with a 2000 engine. I have an OBD scanner it read way differently than my cluster. For example: my OBD reads 190 my cluster says is over heating at 240ish. I found that the previous owner hacked the wires since the 2000 engine doesn't have the sensor in the back of the head, he made a T fitting so I have the sensor that goes to my aux fan and OBD and sensor that goes to my cluster all connected to my tsat housing. So my question is that why my cluster is reading way off? or because the sensor is bad?

 

Use an IR heat gun to check the temps.

 

Possible incorrect sender

 

IR guns are not expensive and can be kinda fun to use!

https://www.amazon.com/s/ref=nb_sb_s...te%2Caps%2C142

 

The temp gauge gets messages over CCDN comms bus to decide where to position itself (it is not a thermometer, its more of an indicator, and should never be used for actual temperature measurements. Read the FSM for more details).

Your OBD2 scanner gets its data from the ECU. If the dashboard cluster gauge has always had problems, I would guess that it is an incompatibility between the newer ECU that was used with the new motor (I'm assuming that along with the new motor you had to use a newer ECU?), and the older instrument cluster.

Just a theory.