Actually there is a connection from the A/C compressor clutch wiring to
the fuel injection harness to let the ISCM know that the A/C compressor
is activated. You can see it on page 97.141 track 16 near the bottom of
the page.

The ISCM connection is to module pin 2/K on page 97.107, via harness pin
T1k between tracks 41 and 42. An error of omission exists in that this
connection is not more fully spelled out in the diagrams.

Mark

Richard A Jones wrote:
>> The AC compressor engaging sends a signal to the ISCM and increases idle
>> speed a bit when the throttle is closed (assuming the throttle position
>> switch is actually closed).
>
> I think the ISCU just notices the drop in RPM from the AC and
> compensates for it.  The only thing connected to the ISCU in
> that way is the power steering pressure switch.  See Bentley
> 97.107.
>
> The AC is 97.140 & 141 and there is no connection back to
> the ISCU.  The only thing the AC relay tells is the radiator
> fan--to kick on low speed, at least.
>
> Richard
> '87 Syncro Westy without a waterboxer
>