Page 935 of 1500
Page 936 of 1500
ENGINE COOLING DIAGNOSIS
ENGINE COOLING14-21
STEP 2. Check the fan control relay connector A-10X.
Q: Is the connector in good condition?
YES : Go to Step 3.
NO : Repair the connector or replace the relay box. Then
go to Step 8.
STEP 3. Check the harness wire between fan control relay
connector A-10X terminal 2 and fan controller connector
A-24 terminal 3.
Q: Is the harness wire in good condition?
YES : Go to Step 4.
NO : Repair the damaged harness wire. Then go to Step 8.
Page 937 of 1500
ENGINE COOLING DIAGNOSIS
ENGINE COOLING14-22
STEP 4. Check the fan controller connector A-24,
intermediate connector A-13 and engine-ECU connector
B-21.
Q: Are these connectors in good condition?
YES : Go to Step 5.
NO : Repair or replace the connector. Then go to Step 8.
Page 938 of 1500
ENGINE COOLING DIAGNOSIS
ENGINE COOLING14-23
STEP 5. Check the harness wire between fan controller
connector A-24 terminal 2 and engine-ECU connector
B-21 terminal 71.
Q: Are these harness wires in good condition?
YES : Go to Step 6.
NO : Repair the damaged harness wire. Then go to Step 8.
Page 939 of 1500
ENGINE COOLING DIAGNOSIS
ENGINE COOLING14-24
STEP 6. Check the fan controller.
(1) Disconnect fan controller connector A-24.
(2) Back out connector terminal pin 2 from connector housing.
(3) Reconnect the connector with connector terminal pin 2 still
removed.
(4) Turn the ignition switch to the "ON" position.
(5) Check for the cooling fan operation.
The cooling fan rotates. (with connector terminal pin 2
disconnected)
(6) Check for the cooling fan operation.
Using a suitable probe connect the fan controller termi-
nal 2 at controller side to earth.The cooling fan stops.
(When pin 2 of fan controller is connected to earth)
(7) Turn the ignition switch to the "OFF" position.
(8) Disconnect fan controller connector A-24, and re-locate
connector terminal pin 2 into connector housing.
(9) Reconnect the connector with connector terminal pin 2
installed correctly.
Q: Does the cooling fan rotate? And when the fan
controller pin 2 is connected to the body earth, does
the cooling fan stop?
YES : Go to Step 7.
NO : Replace the fan motor and fan controller (Refer to
14-25). Then go to Step 8.
Page 940 of 1500
ENGINE COOLING DIAGNOSIS
ENGINE COOLING14-25
STEP 7. MUT-III self-diag code
Check if an MPI system self-diag code is set. (Refer to GROUP
13A - Trouble shooting 13A-5)
Q: Diagnosis code set?
YES : Inspection chart for diagnosis code (Refer to GROUP
13A - Trouble shooting 13A-5)
NO : Replace the engine-ECU (Refer to GROUP 13A,
Engine-ECU 13A-675 ) Then go to Step 8 .
STEP 8. Check the symptoms.
Q: Does the radiator fan motor and the condenser fan
motor operate correctly?
YES : This symptom is complete.
NO : Return to Step 1.
INSPECTION PROCEDURE 5: Radiator Fan does not Operate
.
Radiator Fan and Condenser Fan Drive
Circuit
.
TECHNICAL DESCRIPTION
The cause could be a malfunction of the radiator fan
motor or an open circuit between the fan controller
and the radiator fan motor.
.
TROUBLESHOOTING HINTS
Malfunction of radiator fan motor
Malfunction of fan controller
Refer to component locations GROUP-1
Refer to configuration diagrams GROUP-1
Refer to circuit diagrams GROUP-1
DIAGNOSIS
Replace the radiator fan motor and fan controller assembly.
Q: Does the radiator fan operate correctly?
YES : There is no action to be taken?
NO : Repair the wiring harness between the fan controller
and the radiator fan motor.
INSPECTION PROCEDURE 6: Condenser Fan does not Operate
.
Radiator Fan and Condenser Fan Drive
Circuit
.
TECHNICAL DESCRIPTION
The cause could be a malfunction of the condenser
fan motor or fan controller.
.
TROUBLESHOOTING HINTS
Malfunction of condenser fan motor
Malfunction of fan controller
Refer to component locations GROUP-1
Refer to configuration diagrams GROUP-1
Refer to circuit diagrams GROUP-1
Page 941 of 1500
ON-VEHICLE SERVICE
ENGINE COOLING14-26
DIAGNOSIS
STEP 1. Check the condenser fan motor.
Condenser fan motor check. (Refer to GROUP 55, Condenser
and Condenser Fan Motor.
Q: Is the condenser fan motor in good condition?
YES : Go to Step 2.
NO : Replace the condenser fan motor, then go to Step 3.
STEP 2. Check the fan controller.
Refer to 29.
Q: Is the fan controller in good condition?
YES : Go to Step 3.
NO : Replace the fan motor and fan controller (Refer to
14-25). Then go to Step 3.
STEP 3. Check the symptoms.
Q: Do the condenser fan operate?
YES : This symptom is complete.
NO : Return to Step 1.
ON-VEHICLE SERVICE
ENGINE COOLANT LEAK CHECKM1141001000333
When pressure testing the cooling system, slowly
release cooling system pressure to avoid getting
burned by hot coolant.
Be sure to completely clean away any moisture from
the places checked.
When the tester is taken out, be careful not to spill any
coolant.
Be careful when installing and removing the tester and
when testing not to deform the filler neck of the radia-
tor.
1. Check that the coolant level is up to the filler neck. Install a
radiator tester and apply 160 kPa (23 psi) pressure, and
then check for leakage from the radiator hose or
connections.
2. If there is leakage, repair or replace the appropriate part.
Page 942 of 1500
ON-VEHICLE SERVICE
ENGINE COOLING14-27
RADIATOR CAP PRESSURE CHECKM1141001300419
NOTE: Be sure that the cap is clean before testing. Rust or
other foreign material on the cap seal will cause an improper
reading.
1. Use a cap adapter to attach the cap to the tester.
2. Increase the pressure until the indicator of the gauge stops
moving.
Minimum limit: 83 kPa (12 psi)
Standard value: 93
123 kPa (14 18 psi)
3. Replace the radiator cap if the reading does not remain at or
above the limit.
ENGINE COOLANT REPLACEMENTM1141001200478
When removing the radiator cap, use care to avoid
contact with hot coolant or steam. Place a shop towel
over the cap and turn the cap counterclockwise a lit-
tle to let the pressure escape through the vinyl tube.
After relieving the steam pressure, remove the cap by
slowly turning it counterclockwise.
1. Drain the water from the radiator, heater core and engine
after unplugging the radiator drain plug and removing the
radiator cap.
