Preparing for T5.5 install: questions about AC wiring - Bulletin Board

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Preparing for T5.5 install: questions about AC wiring
Posted by Notnoel [Email] (#23) [Profile/Gallery] (more from Notnoel) on Sat, 23 Jun 2018 12:19:17
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I bought the Europarts kit and the install seems straight forward enough, but I am struggling with some issues not addressed by the kit (because it has no AC incorporated). I have a 1988 LH 2.2 turbo.

On another forum, I found instructions that say to hookup the AC, disconnect the AC trigger relay wire from the relay and run that wire to pin 59 of the Trionic ECU (A/C in) and then run a wire from pin 54 of the ECU to the trigger terminal of the AC relay, thus placing the Trionic ECU in charge of operating the ECU. Seems straight forward enough.

Next, I found the Youtube video below and got some good info but still need clarification. In the video, the narrator describes That there are five wires controlling the AC circuit. Of these, three wires going to the old LH2.2 ECU: 1) a blue wire to LH-ECU pin 12 (full throttle cut-off), 2)a red/white wire to LH-ECU pin 16 (AC idle increase), and 3) a green/white switched power wire to LH-ECU pin 18 (ignition on relay). Of the other two wires: 4) the red/gray heavy gauge wire goes to the main power relay which supplies power to the AC relay, and 5) a red wire that provides power to the compressor.

So if I read this correctly I need to do three things:

1) hook-up the heavy wire to power the AC relay,
2) hook-up the red wire to the compressor,
3) and do the AC relay wiring to Trionic pins 54 an 59 as discussed in the first paragraph.

I don't do anything at all with the other three wires. Question 1 - does that seem right?

However, what is confusing to me is the role of wire # 3 discussed above (the green/white ignition on relay), so Question 2 - is the green/white wire the AC trigger wire discussed in the first first paragraph.

Any help is much appreciated!

Youtube: SAAB C900 T5 Conversion / AC Plug Description

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