The "O" button is everything off (including fresh air).
The "black arrow EC/white arrow down" button is fresh air and blower (blower won't work in this setting at low outside temps until engine warms up), and no AC compressor. So, this is heated fresh air or ambient temperature fresh air only, no AC!
The "black arrow up/white arrow down" is the recommended normal setting for cooling and humidity control. Warm air is given priority flow to the feet area, but also comes out the side and center dash vents, and a small amount to the windshield dash vents to keep it clear.
The "white arrow up/white arrow down" is multi level for "clearing a fogged windshield-As soon as the windshield is cleared, reset to normal or EC mode". Warm air may only periodically come from center vents in this mode, depending on interior temperature. Also, "prolonged use of this mode may cause condensation on outside windshield in warm, humid climates". (It does!)
The (almost)last button is defrost, and "sends the maximum amount of heated air to the windshield and side vents, overriding the temperature, fan speed, and air recirculation switches.
Finally, there is a recirculation switch above the main climate control switches with 3 curved arrows making up a circle. Pressing the symbol side of this switch causes outside fresh air to be shut off ( a red light comes on in the switch). The switch shuts itself off (back to fresh air) after 5-2o minutes, and won't work when the EC mode is selected.
(Whew) Hope this helps.
[Edited by JCE on 01-10-2001 at 10:46 PM]
2003 Firemist Red/grey leather SL 500
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1987 Smoke Silver/burgundy mbtex 300E Sportline (SOLD)
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