Using the Helms shop manual, appears to be four temperature sensors in the Cruze 1.4L engine.
One if for ambient located by the left fog lamp, shows ambient temperature on the radio and somehow connected to the AC compressor control.
For coolant, three of them, and was able to locate them on my Cruze.
One is located on the right edge of the radiator, this is good, and explains why the temperature gauge is constant. For years, using the ECT engine sensor to save a buck for radiator fan control, but ended up in constant thermal cycling of the engines between 195 and 235*F. Radiator fan wouldn't kick on until the cooling system was just about ready to blow its cork. And with an aluminum head with seven times the expansion rate of a cast iron block, would get head gasket problems if not even a cracked head.
They claim another one is buried in the thermostat, I know there is a heater in there, but wasn't aware of also a temperature sensor, they call this temperature sensor #1, is shown on one itty bitty circuit diagram, but where it goes from there is anyone's good guess.
The other engine coolant temperature sensor is locate on the water outlet at the lower center of the rear of the engine above the bell housing and is temperature sensor #2. Again, shown on an electrical diagram going into a rectangular box with really not much identification as to what this block is.
We know we have two temperature readouts, on the DTC and the gauge, DTC is just a block really not showing any inputs, and can't even find the analog gauge anywhere, but only plowing through over 3000 pages of constantly repeated safety information. Only option I can see is to test each one, still can't find the resistance versus temperature charts. Ha, replace it with a know good one kind of BS. Not bad if you have a whole bunch of cars to take one out of, but if you do, will also be wrecking those cars as well, can't remove any of the coolant sensors without spilling coolant all over the place.
What a bunch of idiots wrote these manuals, how about a complete fold out circuit diagram even with ranges and voltages, should include scope patterns as well. Solid state, do not test is stupid.
No wonder why these expert mechanics dealer claim they have know nothing.