AC wire on ecu

[SlimLim]

Hi all,

My car is an August 1988 and it doesn't seem to fit in with the pre89 plugs, or post 1989 plugs. So i'm having a hard time identifying some wires.

Is the AC Compressor wire (blue/red) that is connected from the B1 plug to the ecu for the AC relay control or AC amplifier?

Nick

 

[jetjock]

From the factory it connects to pin 11 on the AC Amplifier. Used for idle up.

http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=143

Strikes me it should provide the same functionality connected either place. As long as the the ECU pin sees 12 volts with the AC on. I'd stick with the factory set up though.

 

[SlimLim]

Thanks jetjock. I should add I'm connecting a standalone ecu.

When you press ac on, there should be 12v seen at that wire? I don't seem to be getting that. I haven't connected the ac compressor yet though.

 

[jetjock]

Welcome mate. Yep, 12-14 vdc with AC on. Connector T, pin 10:

http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=49

http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=50

The connector and pin designations may not apply to your car but you get the idea. With the stock ECU the signal actually increases timing so as to prevent idle drop. Course with a standalone it'll be a different story.