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I'm an electron in a HVAC head...

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Old 01-12-2019, 05:18 PM
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FLYVMO
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Default I'm an electron in a HVAC head...

....Please take me through the electric path of these pictured connectors

In all seriousness, can someone explain the current path/source/destination for these 2 connectors on an early vacuum HVAC head(1980 early).
The car has no auto climate control or internal/external temperature sensors, so I just need to wire this as an "independent" system, considering the CEB is not used.
What connects to the 3-pin molex plug and what does it control, and same for the 2-pin switch (microswitch triggered?)
Any help is greatly appreciated!
Carl



Old 01-13-2019, 12:06 AM
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77tony
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Originally Posted by FLYVMO
....Please take me through the electric path of these pictured connectors

In all seriousness, can someone explain the current path/source/destination for these 2 connectors on an early vacuum HVAC head(1980 early).
The car has no auto climate control or internal/external temperature sensors, so I just need to wire this as an "independent" system, considering the CEB is not used.
What connects to the 3-pin molex plug and what does it control, and same for the 2-pin switch (microswitch triggered?)
Any help is greatly appreciated!
Carl


bump^^
Old 01-13-2019, 08:08 AM
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ammonman
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The black/white wire on the three wire Molex plug is +12VDC incoming power to the control unit. The blue/red wire sends power to energize the blower relay while the black/red wire energizes the defrost relay that switches the blower to high speed and powers up the A/C compressor clutch circuit. The microswitch connects to either side of the push button that engages the A/C compressor clutch to turn the A/C on with the defroster regardless if the A/C switch is pressed.
Old 01-13-2019, 02:42 PM
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FLYVMO
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Originally Posted by ammonman

The black/white wire on the three wire Molex plug is +12VDC incoming power to the control unit. The blue/red wire sends power to energize the blower relay while the black/red wire energizes the defrost relay that switches the blower to high speed and powers up the A/C compressor clutch circuit. The microswitch connects to either side of the push button that engages the A/C compressor clutch to turn the A/C on with the defroster regardless if the A/C switch is pressed.
Sweetness!

Very clearly explained, and very much appreciated!

Cheers!
Carl



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