temp gauge not reading after replacing sending unit

[feedthemonkey]

I bought my 93 EX for $1 as a project car for learning. Let the learning begin!

I put in a new radiator, hoses, thermostat and sending unit. Dash temp gauge won't wake up (it was reading, albeit low, before my project). It's not moving at all now. I let the vehicle run for a few minutes. Nothing. Let it run longer?

I pulled the sending unit and checked that ohms are changing based on temperature. (so, sending unit is good?). Maybe I wiggled a wire loose during the project?

How might I go about diagnosing this one?

(also, what's the other sensor attached by the water outlet? If I'm facing water outlet, the temp sensor is at 11 o'clock. What's that at 2 o'clock? ...a bit larger than sending unit and has wire connection coming out)

 

[Turdle]

Front of vehicle higher than rear, to allow air out. I think it needs a burp.

Turn heat on hot. Floor to fill heater core

 

[feedthemonkey]

Front of vehicle higher than rear, to allow air out. I think it needs a burp.

Turn heat on hot. Floor to fill heater core

Thanks a lot! That seemed to do it. Gauge responds. My previous attempt at burping was some timid squeezes on the upper hose.

 

[Turdle]

Yes, beware of this. Low coolant may render gauge useless.

 

[LG57]

The other temp sensor is the input to the computer.