RM3660EC _51 Engine / Hybrid System _080775 8ZR-FXE COOLING _0392612 COOLING FAN SYSTEM J

8ZR-FXE COOLING  COOLING FAN SYSTEM  Cooling Fan Circuit  


DESCRIPTION

The ECM turns on or off the fan relays using signals calculated from the engine coolant temperature, air conditioning switch (on/off), air conditioning refrigerant pressure, engine speed and vehicle speed signals.

The ECM switches the circuit of the cooling fan motors between series and parallel by turning on or off the fan relays in order to control the speed of the cooling fan motors in two steps.

WIRING DIAGRAM

A538494E07
0.49,7.781 1.49,8.208 1,0.427 10 false Auxiliary 3.323,7.74 5.365,8.229 2.042,0.49 10 false EFI-MAIN NO. 1 4.073,7.354 5.927,7.604 1.854,0.25 10 false 2 3.365,6.896 5.219,7.146 1.854,0.25 10 false 5 4.073,6.906 5.927,7.156 1.854,0.25 10 false 3 3.375,7.365 5.229,7.615 1.854,0.25 10 false 1 5.719,7.333 6.083,7.583 0.365,0.25 10 false 27 5.979,7.479 6.51,7.813 0.531,0.333 10 false MREL 6.24,8.146 6.771,8.479 0.531,0.333 10 false A46 6.219,8.323 6.75,8.656 0.531,0.333 10 false ECM 0.635,7.219 2.49,7.469 1.854,0.25 10 false BATT-MAIN 1.802,6.219 3.656,6.469 1.854,0.25 10 false EFI NO. 3 0.344,4.01 2.198,4.26 1.854,0.25 10 false DC/DC 2.542,2.667 4.396,2.917 1.854,0.25 10 false FAN NO. 1 4.344,4.792 6.198,5.042 1.854,0.25 10 false A4 4.333,4.958 5.083,5.458 0.75,0.5 10 false Cooling Fan Motor RH 3.979,4.667 5.833,4.917 1.854,0.25 10 false 2 3.969,5.146 5.823,5.396 1.854,0.25 10 false 1 5.979,4.385 6.51,4.719 0.531,0.333 10 false FANH 5.719,4.25 6.25,4.583 0.531,0.333 10 false 43 2.469,4.26 3,4.594 0.531,0.333 10 false 1 3.146,4.26 3.677,4.594 0.531,0.333 10 false 2 2.479,3.833 3.01,4.167 0.531,0.333 10 false 5 2.885,3.667 3.219,4 0.333,0.333 10 false 4 3.146,3.833 3.479,4.167 0.333,0.333 10 false 3 2.542,4.635 4.396,4.885 1.854,0.25 10 false FAN NO. 2 2.563,1 4.417,1.25 1.854,0.25 10 false FAN NO. 3 4.74,1.063 6.594,1.313 1.854,0.25 10 false A5 4.74,1.219 5.49,1.719 0.75,0.5 10 false Cooling Fan Motor LH 4.354,0.979 6.208,1.229 1.854,0.25 10 false 2 4.344,1.427 6.198,1.677 1.854,0.25 10 false 1 2.458,2.302 2.99,2.635 0.531,0.333 10 false 1 3.156,2.302 3.688,2.635 0.531,0.333 10 false 2 2.458,1.896 2.792,2.229 0.333,0.333 10 false 3 3.167,1.885 3.698,2.219 0.531,0.333 10 false 5 1.188,0.427 3.042,0.677 1.854,0.25 10 false FAN NO. 2 1.208,2.125 3.063,2.375 1.854,0.25 10 false FAN NO. 1 2.458,0.198 2.792,0.531 0.333,0.333 10 false 3 3.156,0.188 3.688,0.521 0.531,0.333 10 false 5 3.146,0.646 3.677,0.979 0.531,0.333 10 false 2 2.458,0.646 2.99,0.979 0.531,0.333 10 false 1 5.969,0.74 6.5,1.073 0.531,0.333 10 false FANL 5.688,0.615 6.219,0.948 0.531,0.333 10 false 42 0.49,7.927 1.49,8.354 1,0.427 10 false Battery 1.542,7.208 3.583,7.698 2.042,0.49 10 false EFI-MAIN NO. 1

CAUTION / NOTICE / HINT

NOTICE:
·

Inspect the fuses for circuits related to this system before performing the following procedure.

·

Before replacing the ECM, refer to Service Bulletin.



PROCEDURE

1.PERFORM ACTIVE TEST USING GTS (CONTROL THE ENGINE COOLING FAN)
a.

Connect the GTS to the DLC3.


b.

Turn the ignition switch to ON (IG)


c.

Turn the GTS on.


d.

Enter the following menus: Powertrain / Engine / Active Test / Control the Engine Cooling Fan.

Powertrain > Engine > Active Test
Tester Display
Control the Engine Cooling Fan
50004 372 26

e.

Perform the Active Test according to the display on the GTS.

OK:
Active Tester Operation Fan Operation
HIGH Cooling fans high speed operate
LOW Cooling fans low speed operate
OFF Cooling fans stop



Result:
Proceed to
OK
NG



OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

Click hereEngine / Hybrid System>8ZR-FXE (COOLING)>COOLING FAN SYSTEM>PROBLEM SYMPTOMS TABLE


NG

2.CHECK HARNESS AND CONNECTOR (FANL - FANH POWER SOURCE)
2.CHECK HARNESS AND CONNECTOR (FANL - FANH POWER SOURCE)
a.

Disconnect the A46 ECM connector.


b.

Turn the ignition switch to ON (IG)


c.

Measure the voltage according to the value(s) in the table below.

Standard Voltage:
Tester Connection Condition Specified Condition
A46-43 (FANH) - Body ground Ignition switch ON 11 to 14 V
A46-42 (FANL) - Body ground Ignition switch ON 11 to 14 V



Result:
Proceed to
OK
NG



OK

3.CHECK HARNESS AND CONNECTOR (FAN NO. 1 RELAY AND FAN NO. 3 RELAY POWER SOURCE CIRCUIT)

NG

12.INSPECT COOLING FAN RELAY (FAN NO. 1, FAN NO. 2 AND FAN NO. 3)
3.CHECK HARNESS AND CONNECTOR (FAN NO. 1 RELAY AND FAN NO. 3 RELAY POWER SOURCE CIRCUIT)
a.

Remove the FAN NO. 1 relay and FAN NO. 3 relay from the No. 1 engine room relay block and No. 1 junction block assembly.


b.

Measure the voltage according to the value(s) in the table below.

Standard Voltage:
Tester Connection Condition Specified Condition
3 (FAN NO. 1 relay) - Body ground Always 11 to 14 V
3 (FAN NO. 3 relay) - Body ground Always 11 to 14 V



Result:
Proceed to
OK
NG



OK

4.INSPECT COOLING FAN RELAY (FAN NO. 1, FAN NO. 2 AND FAN NO. 3)

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR (FAN NO. 1 RELAY AND FAN NO. 3 RELAY POWER SOURCE CIRCUIT)

4.INSPECT COOLING FAN RELAY (FAN NO. 1, FAN NO. 2 AND FAN NO. 3)
a.

Inspect the FAN NO. 1 relay, FAN NO. 2 relay and FAN NO. 3 relay.

Click hereEngine / Hybrid System>8ZR-FXE (COOLING)>RELAY>ON-VEHICLE INSPECTION


Result:
Result Proceed to
OK A
NG (FAN NO. 1 relay) B
NG (FAN NO. 2 relay) C
NG (FAN NO. 3 relay) D



A

5.CHECK HARNESS AND CONNECTOR (FAN NO. 2 RELAY - BODY GROUND)

B

REPLACE FAN NO. 1 RELAY

C

REPLACE FAN NO. 2 RELAY

D

REPLACE FAN NO. 3 RELAY

5.CHECK HARNESS AND CONNECTOR (FAN NO. 2 RELAY - BODY GROUND)
a.

Remove the FAN NO. 2 relay from the No. 1 engine room relay block and No. 1 junction block assembly.


b.

Measure the resistance according to the value(s) in the table below.

Standard Resistance (Check for Open):
Tester Connection Condition Specified Condition
5 (FAN NO. 2 relay) - Body ground Always Below 1 Ω



Result:
Proceed to
OK
NG



OK

6.INSPECT COOLING FAN MOTOR RH

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR (FAN NO. 2 RELAY - BODY GROUND)

6.INSPECT COOLING FAN MOTOR RH
a.

Inspect the cooling fan motor RH.

Click hereEngine / Hybrid System>8ZR-FXE (COOLING)>COOLING FAN MOTOR>ON-VEHICLE INSPECTION


Result:
Proceed to
OK
NG



OK

7.CHECK HARNESS AND CONNECTOR (COOLING FAN MOTOR RH - BODY GROUND)

NG

REPLACE COOLING FAN MOTOR RH

Click hereEngine / Hybrid System>8ZR-FXE (COOLING)>COOLING FAN MOTOR>REMOVAL


7.CHECK HARNESS AND CONNECTOR (COOLING FAN MOTOR RH - BODY GROUND)
a.

Disconnect the A4 cooling fan motor RH connector.


b.

Measure the resistance according to the value(s) in the table below.

Standard Resistance (Check for Open):
Tester Connection Condition Specified Condition
A4-1 - Body ground Always Below 1 Ω



Result:
Proceed to
OK
NG



OK

8.CHECK HARNESS AND CONNECTOR (FAN NO. 1 RELAY AND FAN NO. 2 RELAY - COOLING FAN MOTOR RH)

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR (COOLING FAN MOTOR RH - BODY GROUND)

8.CHECK HARNESS AND CONNECTOR (FAN NO. 1 RELAY AND FAN NO. 2 RELAY - COOLING FAN MOTOR RH)
a.

Disconnect the A4 cooling fan motor RH connector.


b.

Remove the FAN NO. 1 relay and FAN NO. 2 relay from the No. 1 engine room relay block and No. 1 junction block assembly.


c.

Measure the resistance according to the value(s) in the table below.

Standard Resistance (Check for Open):
Tester Connection Condition Specified Condition
A4-2 - 5 (FAN NO. 1 relay) Always Below 1 Ω
A4-2 - 4 (FAN NO. 2 relay) Always Below 1 Ω


Standard Resistance (Check for Short):
Tester Connection Condition Specified Condition
A4-2 or 5 (FAN NO. 1 relay) - Body ground Always 10 kΩ or higher
A4-2 or 4 (FAN NO. 2 relay) - Body ground Always 10 kΩ or higher



Result:
Proceed to
OK
NG



OK

9.INSPECT COOLING FAN MOTOR LH

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR (FAN NO. 1 RELAY AND FAN NO. 2 RELAY - COOLING FAN MOTOR RH)

9.INSPECT COOLING FAN MOTOR LH
a.

Inspect the cooling fan motor LH.

Click hereEngine / Hybrid System>8ZR-FXE (COOLING)>COOLING FAN MOTOR>ON-VEHICLE INSPECTION


Result:
Proceed to
OK
NG



OK

10.CHECK HARNESS AND CONNECTOR (FAN NO. 2 RELAY AND FAN NO. 3 RELAY - COOLING FAN MOTOR LH)

NG

REPLACE COOLING FAN MOTOR LH

Click hereEngine / Hybrid System>8ZR-FXE (COOLING)>COOLING FAN MOTOR>REMOVAL


10.CHECK HARNESS AND CONNECTOR (FAN NO. 2 RELAY AND FAN NO. 3 RELAY - COOLING FAN MOTOR LH)
a.

Disconnect the A5 cooling fan motor LH connector.


b.

Remove the FAN NO. 2 relay and FAN NO. 3 relay from the No. 1 engine room relay block and No. 1 junction block assembly.


c.

Measure the resistance according to the value(s) in the table below.

Standard Resistance (Check for Open):
Tester Connection Condition Specified Condition
A5-1 - 3 (FAN NO. 2 relay) Always Below 1 Ω
A5-2 - 5 (FAN NO. 3 relay) Always Below 1 Ω


Standard Resistance (Check for Short):
Tester Connection Condition Specified Condition
A5-1 or 3 (FAN NO. 2 relay) - Body ground Always 10 kΩ or higher
A5-2 or 5 (FAN NO. 3 relay) - Body ground Always 10 kΩ or higher



Result:
Proceed to
OK
NG



OK

11.CHECK HARNESS AND CONNECTOR (FAN NO. 1 RELAY - FAN NO. 2 RELAY)

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR (FAN NO. 2 RELAY AND FAN NO. 3 RELAY - COOLING FAN MOTOR LH)

11.CHECK HARNESS AND CONNECTOR (FAN NO. 1 RELAY - FAN NO. 2 RELAY)
a.

Remove the FAN NO. 1 and FAN NO. 2 relay from the No. 1 engine room relay block and No. 1 junction block assembly.


b.

Measure the resistance according to the value(s) in the table below.

Standard Resistance (Check for Open):
Tester Connection Condition Specified Condition
1 (FAN NO. 1 relay) - 1 (FAN NO. 2 relay) Always Below 1 Ω
2 (FAN NO. 1 relay) - 2 (FAN NO. 2 relay) Always Below 1 Ω


Standard Resistance (Check for Short):
Tester Connection Condition Specified Condition
1 (FAN NO. 1 relay) or 1 (FAN NO. 2 relay) - Body ground Always 10 kΩ or higher
2 (FAN NO. 1 relay) or 2 (FAN NO. 2 relay) - Body ground Always 10 kΩ or higher



Result:
Proceed to
OK
NG



OK

REPLACE ECM

Click hereEngine / Hybrid System>8ZR-FXE (ENGINE CONTROL)>ECM>REMOVAL


NG

REPAIR OR REPLACE HARNESS OR CONNECTOR (FAN NO. 1 RELAY AND FAN NO. 2 RELAY - ECM)

12.INSPECT COOLING FAN RELAY (FAN NO. 1, FAN NO. 2 AND FAN NO. 3)
a.

Inspect the FAN NO. 1 relay, FAN NO. 2 relay and FAN NO. 3 relay.

Click hereEngine / Hybrid System>8ZR-FXE (COOLING)>RELAY>ON-VEHICLE INSPECTION


Result:
Result Proceed to
OK A
NG (FAN NO. 1 relay) B
NG (FAN NO. 2 relay) C
NG (FAN NO. 3 relay) D



A

13.CHECK HARNESS AND CONNECTOR (FAN NO. 1 RELAY, FAN NO. 2 RELAY AND FAN NO. 3 RELAY POWER SOURCE CIRCUIT)

B

REPLACE FAN NO. 1 RELAY

C

REPLACE FAN NO. 2 RELAY

D

REPLACE FAN NO. 3 RELAY

13.CHECK HARNESS AND CONNECTOR (FAN NO. 1 RELAY, FAN NO. 2 RELAY AND FAN NO. 3 RELAY POWER SOURCE CIRCUIT)
a.

Remove the FAN NO. 1 relay and FAN NO. 2 relay and FAN NO. 3 relay from the No. 1 engine room relay block and No. 1 junction block assembly.


b.

Measure the voltage according to the value(s) in the table below.

Standard Voltage:
Tester Connection Condition Specified Condition
1 (FAN NO. 1 relay) - Body ground Ignition switch ON 11 to 14 V
1 (FAN NO. 2 relay) - Body ground Ignition switch ON 11 to 14 V
1 (FAN NO. 3 relay) - Body ground Ignition switch ON 11 to 14 V



Result:
Proceed to
OK
NG



OK

REPAIR OR REPLACE HARNESS OR CONNECTOR (FAN NO. 1 RELAY, FAN NO. 2 RELAY AND FAN NO. 3 RELAY - ECM)

NG

14.CHECK HARNESS AND CONNECTOR (FAN NO. 1 RELAY, FAN NO. 2 RELAY AND FAN NO. 3 RELAY - EFI-MAIN NO.1 RELAY)
14.CHECK HARNESS AND CONNECTOR (FAN NO. 1 RELAY, FAN NO. 2 RELAY AND FAN NO. 3 RELAY - EFI-MAIN NO.1 RELAY)
a.

Remove the EFI-MAIN No. 1 relay, FAN NO. 1 relay, FAN NO. 2 relay and FAN NO. 3 relay from the No. 1 engine room relay block and No. 1 junction block assembly.


b.

Measure the resistance according to the value(s) in the table below.

Standard Resistance (Check for Open):
Tester Connection Condition Specified Condition
1 (FAN NO. 1 relay) - 5 (EFI-MAIN No. 1 relay) Always Below 1 Ω
1 (FAN NO. 2 relay) - 5 (EFI-MAIN No. 1 relay) Always Below 1 Ω
1 (FAN NO. 3 relay) - 5 (EFI-MAIN No. 1 relay) Always Below 1 Ω


Standard Resistance (Check for Short):
Tester Connection Condition Specified Condition
1 (FAN NO. 1 relay) or 5 (EFI-MAIN No. 1 relay) - Body ground Always 10 kΩ or higher
1 (FAN NO. 2 relay) or 5 (EFI-MAIN No. 1 relay) - Body ground Always 10 kΩ or higher
1 (FAN NO. 3 relay) or 5 (EFI-MAIN No. 1 relay) - Body ground Always 10 kΩ or higher



Result:
Proceed to
OK
NG



OK

15.INSPECT EFI-MAIN NO.1 RELAY

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR (FAN NO. 1 RELAY, FAN NO. 2 RELAY AND FAN NO. 3 RELAY - EFI-MAIN NO.1 RELAY)

15.INSPECT EFI-MAIN NO.1 RELAY
a.

Inspect the EFI-MAIN No. 1 relay.

Click hereEngine / Hybrid System>8ZR-FXE (ENGINE CONTROL)>RELAY>ON-VEHICLE INSPECTION


Result:
Proceed to
OK
NG



OK

16.CHECK HARNESS AND CONNECTOR (EFI-MAIN NO.1 RELAY POWER SOURCE CIRCUIT)

NG

REPLACE EFI-MAIN NO.1 RELAY

16.CHECK HARNESS AND CONNECTOR (EFI-MAIN NO.1 RELAY POWER SOURCE CIRCUIT)
a.

Remove the EFI-MAIN No. 1 relay from the No. 1 engine room relay block and No. 1 junction block assembly.


b.

Measure the voltage according to the value(s) in the table below.

Standard Voltage:
Tester Connection Condition Specified Condition
5 (EFI-MAIN No. 1 relay) - Body ground Always 11 to 14 V



Result:
Proceed to
OK
NG



OK

17.CHECK HARNESS AND CONNECTOR (EFI-MAIN NO.1 RELAY - BODY GROUND)

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR (EFI-MAIN NO.1 RELAY POWER SOURCE CIRCUIT)

17.CHECK HARNESS AND CONNECTOR (EFI-MAIN NO.1 RELAY - BODY GROUND)
a.

Remove the EFI-MAIN No. 1 relay from the No. 1 engine room relay block and No. 1 junction block assembly.


b.

Measure the resistance according to the value(s) in the table below.

Standard Resistance:
Tester Connection Condition Specified Condition
1(EFI-MAIN No. 1 relay) - Body ground Always Below 1 Ω



Result:
Proceed to
OK
NG



OK

18.CHECK HARNESS AND CONNECTOR (ECM - EFI-MAIN NO.1 RELAY)

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR (EFI-MAIN NO.1 RELAY - BODY GROUND)

18.CHECK HARNESS AND CONNECTOR (ECM - EFI-MAIN NO.1 RELAY)
a.

Disconnect the A46 ECM connector.


b.

Remove the EFI-MAIN No. 1 relay from the No. 1 engine room relay block and No. 1 junction block assembly.


c.

Measure the resistance according to the value(s) in the table below.

Standard Resistance (Check for Open):
Tester Connection Condition Specified Condition
A46-27 (MREL) - 2 (EFI-MAIN No. 1 relay) Always Below 1 Ω


Standard Resistance (Check for Short):
Tester Connection Condition Specified Condition
A46-27 (MREL) or 2 (EFI-MAIN No. 1 relay) - Body ground Always 10 kΩ or higher



Result:
Proceed to
OK
NG



OK

REPLACE ECM

Click hereEngine / Hybrid System>8ZR-FXE (ENGINE CONTROL)>ECM>REMOVAL


NG

REPAIR OR REPLACE HARNESS OR CONNECTOR (ECM - EFI-MAIN NO.1 RELAY)