SW20 MR2 AC clutch control
After installation of the MR2LINK V3 pnp ECU, the AC on my MR2 had stopped working. After spending a long time troubleshooting and looking up factory electrical diagrams and research on how the AC circuit works we noted the AC clutch is controlled directly by the AC amplifier unit self and for the output from the ECU, an ON position actually tells the AC amplifier to disengage the clutch (presumably at high RPM to protect the compressor) rather than sending out a signal to engage the clutch.
I know this is an old thread but thought I should post my solution to this problem. What I've noticed is the ECU doesn't have any control over the AC clutch, it just reacts to the AC amplifier activating the clutch. This means if you've done away with the standard Idle up valve (as I have) the idle will stumble when the clutch comes in becase theres no delay between the AC request and the clutch being energised, What I did was disconnected the ACT and MGC from the AC amplifier connector and w