4kq air conditioning

[Roa, Greg]

Hello,
On my 86' 4kq, the air conditioning will not turn on.  I believe the system
is leaky, and it is low on freon.  Question is, when the air conditioning
switch is turned on, the switch lights up, and I can hear the engine speed
up.  I know the car is supposed to do this, but the clutch for the
compressor does not engage, and the radiator fan does not turn on either.
Would the low pressure switch cause this behavior, or is this something
else?
Thanks,

Greg Roa
Cincinnati, OH
86' 4kcsq
93' 90CS
83' 944