p259/stepper input -- sensor signal wire +12v when not in use...?

[Joof]

I am trying to wire A/C into my VEMS from BMW E36 M50B30.  Stock relies on pressure sensor to trip compressor relay.  I can wire the two together and it works but I would like to utilize VEMS N2O output to control based upon TPS, MAP etc.

The compressor relay is fine to wire to p259 from an amperage standpoint but I am not sure about the pressure sensor.

When off, it shows full system voltage - when it receives power from A/C cabin button it draws ~.2 Amp and has a voltage of around .45 Volts

I know the current side of the sensor is fine for a p259 channel (< 300 mA), but when it is off (that is A/C cabin button is off) it has +12v.  Can the sensor be hooked up to a p259 or must I sacrifice my last ignition output (that I am saving for boost control)? 

I know I have seen something similar regarding fuel pump relays - that when off you see system voltage or something to that effect but I want to confirm whether or not +12v there will kill the board?

May seem simple, but I am not terribly well versed with this type of thing - if anyone has any input I would really appreciate it.

Thanks!

[mattias]

Read this thread about "A/C and idle control" ?
http://www.vemssupport.com/forum/index.php/topic,1936.0.html

[Joof]

Mattias, thanks for the reply.

I have read that, are you referring to http://www.vemssupport.com/forum/index.php/topic,1936.msg19508.html#msg19508?

Are you saying it needs a relay to invert?

I have no issue with it causing stalling when wired separate from VEMS as I am currently employing idle ignition advance + IAC (works perfect)