Mitsubishi 3000GT Service Manual page 1227

Condenser fan does not
operate when the air
conditioning is activated
HEATERS AND MANUAL
AIR CONDITIONING
AIR CONDITIONING COMPRESSOR LOCK
CONTROLLER
Operation
(1) The A/C compressor lock controller compares compressor
rpm
or the compressor has seized. If the rpm difference be-
tween the engine and compressor exceed 92 % for more
than three seconds, the A/C compressor lock controller
turns off the magnetic clutch relay which opens the mag-
netic clutch circuit.
(2) when a signal is received from the ECU requesting com-
pressor operation, the A/C compressor lock controller
will energize the magnetic clutch relay to determine if
the compressor drive belt is slipping. If the speed differ-
ence between the engine and compressor indicates the
belt is slipping, the A/C compressor lock controller will
de-energize the magnetic clutch relay.
TSB
Revision
with engine rpm to determine if the drive belt is slipping