I am new to the Forum and am impressed with the knowledge contained here in. While we have a 2014 ES350, which we are totally satisfied with, our Grandson has a 92 LS400.

Was able to fix his CEL, OBD code 71, after reading the posts in this Forum, which is the reason I joined. He has another problem, the Temperature Gauge is not working. He took it to a local shop and they said it was the Instrument Cluster and would take $1,000 to repair. The engine appears to be running at the proper temperature per my Infra Red thermometer.

Before investing in an Instrument Cluster I want to eliminate the Temperature Sender and wiring. I will appreciate the following info if any has it:

1. What is the "cold" and "hot" resistance of the Temperature Sender.

2. What voltage should I read at the end of the connecting wire to the Temperature Sender both connected and disconnected.

3. Will it be safe to connect the wire to Temperature Sender to Gnd to see if the Gauge deflects.

The above is all I can think of to do but if you have any suggestions/advice I will appreciate your input

 

This should be moved to the regular forum where you can get more help.

 

Check the coolant level to be sure it is at the proper level before going through all the electric tests.Did you drain the coolant recently?If so,the level may show full but a large bubble of air may have developed and is not allowing the coolant to register on the gauge.

 

UNCNOR, the Temperature Sender is reading both the Coolant temperature and the temperature of the engine metal it is screwed into. The Gauge should read the higher of the Coolant or Block temperature, hopefully they are the same.


For the above reason I have ruled out low Coolant or air bubble as the metal of the block will still conduct heat.


Thks for your response.