Thread: HVAC Control on Car PC through Serial Port.

Originally Posted by j99vette

I think I need to clarify the question. With what I want to do, could this kit be used as a base for my project and modify it to fit my needs? I was not trying to imply that all of the kits should have those features. I was just wondering if it could be modified slightly for what I need or if I would be better off starting from scratch. Thanks.

Everyone please wait for the DIY manual.. i shall put in there everything this unit is capable of doing.

I am getting the final PCB on 18th so by 22nd there shall be a full DIY manual with pics..

Thanx
Mastero

sweet. btwn do you have any pics of the addon unit for aircon 1 ?

No .. i made it on a beed board.

Mastero

i diddnt see anything about the addon board.. All i need is a schematic, parts list and the code needed to be programmed.

Check post 375 and 381

Cheers
Mastero

This is one of the longest threads I have read so far, and for good reason. I want one. There is only one thing I've got reservations about. I live and Las Vegas, NV. USA. I'd like to try the LM34 method for F vs. C, but much of the year here, it's over 99F, in fact in car temps reach around 150F. I see the 8 segment display is 2 digit. Is that the only limitation to 3 digit temp display. Can the UI be modified to display three digits? Or, is this a harware limit, prior to sending this data to the serial port? I figure I could find a harware solution interface the 8 seg display. Which leaves me with the software/serial side, wondering... can it be done?

I hvae been thinking about this, and I believ I remember Mastro saying that the software was written in VB, if so we could add a few lines to do the conversion and desplay F on the LCD, the LED (which I would not even hook up) would still read C if it is not controlled by the front end, but by the board/thermal sensor

That would sell me on the whole deal. Converting C to F in the software wouldn't require any more information or the LM34. Correct?
And I gather that there are no variable inputs in the upgrade. I would like to control a factory servo amplifier as seen in the drawing below, and have more than a preset number of temps to work with. The software could have a linear proportionality setting, using max and minimum volts and temps.
And:
Can the 9 outputs be used in place of the servo outputs in aircon2? e.g. to discreetly control individual vacuum solenoids. Will the software support that?
It would be nice to have another variable output for blower control (bypassing the resistor divider network), to get that modern 'soft start' and ramp effect.

I have similar drawings and HVAC vac diags for most pre-2004/post-1985 applications. if the requests don't get out of control. Just pm or email me. Please, this thread is long enough, as-is, I will not reply to public requests for such in mastero's thread.

If you have the schematics to a 1998 Cavalier z24, I could really use those. I tried to send you an email. Not sure if you got it

Happy Holloween eveyone (So I'm a day late and dollar short!)