You will definitely have the use of the Air-con system with the stock ECU removed or disabled bacause the Air-con is not controlled by the ECU, instead it has an individual switch engaging the A/C pump.
What the ECU does do that relates to the A/C is that it compensates for battery voltage drops, like when the A/C is switched on, more fuel is needed at idle to maintain a stable idle.
<hr width=60% noshade size=1 align=left>Tiburon Turbo 350KW and 700NM AKA Black Monster
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