No question about the moisture sensor, from the Cruze shop manual:
"
Windshield Temperature and Inside Moisture Sensor
The windshield temperature and inside moisture sensor includes the relative humidity sensor, windshield temperature sensor and humidity sensing element temperature sensor.
This sensor assembly provides information about:
• | Relative humidity level at windshield (compartment side) |
• | Temperature of the windshield inside (compartment side) |
• | Temperature of the humidity sensor element |
The relative humidity sensor measures the relative humidity of the compartment side of the windshield. It also detects the temperature of the windshield surface on the passenger compartment side. Both values are used as control inputs for the HVAC control module application to calculate the fog risk on windshield compartment side and ability to reduce fuel consumption by decreasing A/C compressor power to a minimum without causing any fog. The sensor will also enable partial recirculation mode in order to improve heat-up performance of the passenger compartment under cold ambient temperature conditions without the risk of mist build-up on the windshield. The humidity sensor element temperature sensor supplies the temperature of the humidity sensor element. It is only needed if the thermal contact between the humidity sensing element and the inside windshield surface is not sufficient."
If I can go back to 1965, with proven silicon transistors and an engineering management headed by all mechanical engineers, was absolutely impossible to convince them to replace ignition or voltage regulator points with a transistor that could switch trillion of times without failure. Wasn't done until the 1972 model year with a two transistor circuit using NASA thick film technology.
How that has changed and how I have changed over the years. With some vehicles having over 488 pages of solid state, do not test circuit diagrams, would be happy to go back to just ignition points when you run into problems.
For some strange reason, back in about the mid-60's when automatic climate control first came out, did permit using one transistor to operate the new blend door motor circuit. Ha, a one transistor automatic climate control system, rest was all electromechanical. Use to like those, you could see what was going on.
04 Cavalier used an old fashion cable system for the mode and blend doors, wife forced it when the doors were frozen and bent a cable, but that was only a 12 buck and five minute repair. Told her not to do that, running the engine for about 2-3 minutes is enough to make switching modes easy.
Previous ACC systems used brushed motors that would burn up if stalled. I see the Cruze is using all stepping motors, if stalled, they normally don't burn up, just don't step. Cavalier also used fixed resistors for the blower motor speeds, again 12 bucks if they burn up. Cruze uses a power MOSFET PWM motor control that runs 112 bucks. Hope this time if the blower motor freezes up, blows the fuse instead of the overpriced module.
Was a bit weary of the Cruze MVAC system, is really nice when it works, just hope, it keeps on working. No, I am not going to take mine all apart and analyze it, still under warranty.
But I do like to know what I have, or got stuck with.