Mitsubishi Eclipse 1990 Service Manual page 605

INSPECTION PROCEDURE 33
Fan motor relay system (Radiator fan, A/C condenser fan)
[Comment]
The fan motor relay is controlled by the power transistor inside the ECM turning ON and OFF.
Disconnect the connector, and measure at the harness
Voltage between 20 and ground, and 21 and ground
Shortcircuit between 20 and ground (Ignition switch:
OK: Radiator fan and condenser fan rotate at high
speed.
Shortcircuit between 21 and ground (Ignition switch:
OK: Radiator fan and condenser fan rotate at low
speed.
Check the radiator fan circuit
Check the condenser fan circuit.
ENGINE (TURBO)
AND
TSB Revision
Probable cause
Malfunction of fan motor relay
Malfunction of fan motor
Improper connector
shortclrcuited
Malfunction of the ECM
Check the
O K
Check trouble symptom.
I
open
Repair