We are just doing finishing touches to Petel T6 ECU installation on YBP Cossie. The car is equipped with aircon and we'd like it to work correctly. It works now, but the compressor works continuously, we are not sure this is correct. Does anyone know how standard car does it? Is it like many other cars that compressor is turned on and off depending on pressure of the refrigerant? Please advise.

 

hello azrael,

my small turbo escort is running on haltech ps1000 ecu and we´ve made the following for the aircon:

-idle up 150-200rpm if aircon is "on"
-at full throttle and over 5000 rpm aircon "off"
-delay time 10sec-so after full throttle the aircon is "on" after this time

if the refrigerent-pressure is too high, the aircon disables itself-also the fan works without the control of the ecu.
the ecu has only the function to switch the enable-output of the ac, as on original eec-IV.

on haltech this is easy to make, cause there is an extra option for an a/c output.

kind regards,
philipp

 

So the pressure switch operates without ECU control through it's own relay?

 

yes, the switch is the "chief"...so your ecu can say "on" with the enable output but if the pressure is too high the ac wouldn´t run.

i have no probs with this conversation, i only made a ecu swap with an adapter...you should find the post of me with pics somewhere here at pf.

 

Great! Thanks for advise. All cars we normally work on have AC fully ECU operated so we weren't sure.