2ZR-FE COOLING  COOLING FAN SYSTEM  Cooling Fan Circuit  


DESCRIPTION

The ECM calculates an appropriate cooling fan speed based on the engine coolant temperature, air conditioning switch condition, refrigerant pressure, engine speed and vehicle speed, and sends the signals to the cooling fan ECU to regulate the cooling fan. The cooling fan ECU controls the cooling fan speed based on the duty ratio signal sent from the ECM. By basing its control on the operating conditions, the ECM can control the fan speed optimally using the cooling fan ECU, achieving both high cooling performance and quietness.

WIRING DIAGRAM

Refer to the System Diagram.

Click hereEngine / Hybrid System>2ZR-FE COOLING>COOLING FAN SYSTEM>SYSTEM DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

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


PROCEDURE

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

Connect the GTS to the DLC3.


b.

Turn the ignition switch to ON.


c.

Turn the GTS on.


d.

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

Powertrain > Engine and ECT > Active Test
Tester Display
Control the Electric Cooling Fan
50004 234 16

e.

Check the operation of the cooling fan while operating it using the GTS.

OK:
GTS Operation Fan Operation
ON Cooling fan operates
OFF Cooling fan stops



Result:
Result Proceed to
OK A
NG (Cooling fan does not operate) B
NG (Cooling fan does not stop) C



A

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

Click hereEngine / Hybrid System>2ZR-FE COOLING>COOLING FAN SYSTEM>PROBLEM SYMPTOMS TABLE


B

2.CHECK COOLING FAN SYSTEM

C

11.CHECK HARNESS AND CONNECTOR (ECM - COOLING FAN ECU)
2.CHECK COOLING FAN SYSTEM
a.

Disconnect the A40 ECM connector.


b.

Turn the ignition switch to ON.


c.

Check the operation of the cooling fan.

OK:

Cooling fan operates.



Result:
Proceed to
OK
NG



OK

REPLACE ECM

Click hereEngine / Hybrid System>2ZR-FE ENGINE CONTROL>ECM>REMOVAL


NG

3.INSPECT COOLING FAN MOTOR
3.INSPECT COOLING FAN MOTOR
a.

Inspect the cooling fan motor.

Click hereEngine / Hybrid System>2ZR-FE COOLING>COOLING FAN MOTOR>ON-VEHICLE INSPECTION


Result:
Proceed to
OK
NG



OK

4.CHECK TERMINAL VOLTAGE (POWER SOURCE CIRCUIT)

NG

REPLACE COOLING FAN MOTOR

Click hereEngine / Hybrid System>2ZR-FE COOLING>COOLING FAN MOTOR>REMOVAL


4.CHECK TERMINAL VOLTAGE (POWER SOURCE CIRCUIT)
A266912C06
0.292,1.865 0.625,2.125 0.333,0.26 1.083,2.813 1.354,2.104 false 2.417,2.823 2.104,2.115 false 0.26,0.281 0.573,0.479 0.313,0.198 10 false *a 0.333,1.917 0.635,2.115 0.302,0.198 10 false A31 0.948,2.885 1.25,3.104 0.302,0.219 10 false +B1 2.375,2.906 2.688,3.104 0.313,0.198 10 false E1
*a Front view of wire harness connector
(to Cooling Fan ECU)


a.

Disconnect the A31 cooling fan ECU connector.


b.

Turn the ignition switch to ON.


c.

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

Standard Voltage:
Tester Connection Condition Specified Condition
A31-1 (+B1) - A31-3 (E1) Ignition switch ON 11 to 14 V



Result:
Proceed to
OK
NG



OK

5.CHECK HARNESS AND CONNECTOR (ECM - COOLING FAN ECU)

NG

6.CHECK HARNESS AND CONNECTOR (COOLING FAN ECU - BODY GROUND)
5.CHECK HARNESS AND CONNECTOR (ECM - COOLING FAN ECU)
a.

Disconnect the A40 ECM connector.


b.

Disconnect the A31 cooling fan ECU connector.


c.

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

Standard Resistance (Check for Short):
Tester Connection Condition Specified Condition
A40-45 (RFC) or A31-2 (SI) - Body ground Always 10 kΩ or higher



Result:
Proceed to
OK
NG



OK

REPLACE COOLING FAN ECU

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

6.CHECK HARNESS AND CONNECTOR (COOLING FAN ECU - BODY GROUND)
a.

Disconnect the A31 cooling fan ECU connector.


b.

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

Standard Resistance (Check for Open):
Tester Connection Condition Specified Condition
A31-3 (E1) - Body ground Always Below 1 Ω



Result:
Proceed to
OK
NG



OK

7.INSPECT FAN NO. 1 RELAY

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

7.INSPECT FAN NO. 1 RELAY
a.

Inspect the FAN NO. 1 relay.

Click hereEngine / Hybrid System>2ZR-FE COOLING>RELAY>ON-VEHICLE INSPECTION


Result:
Proceed to
OK
NG



OK

8.INSPECT ENGINE ROOM RELAY BLOCK AND JUNCTION BLOCK ASSEMBLY (FAN NO. 1 RELAY)

NG

REPLACE FAN NO. 1 RELAY

8.INSPECT ENGINE ROOM RELAY BLOCK AND JUNCTION BLOCK ASSEMBLY (FAN NO. 1 RELAY)
A314448C01
0.125,0.104 0.438,0.302 0.313,0.198 10 false *1 0.198,1.854 0.51,2.052 0.313,0.198 10 false *2
*1 Engine Room Relay Block and Junction Block Assembly
*2 FAN NO. 1 Relay


a.

Remove the FAN NO. 1 relay from the engine room relay block and 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



Result:
Proceed to
OK
NG



OK

9.CHECK HARNESS AND CONNECTOR (FAN NO. 1 RELAY - COOLING FAN ECU)

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - FAN NO. 1 RELAY)

9.CHECK HARNESS AND CONNECTOR (FAN NO. 1 RELAY - COOLING FAN ECU)
a.

Disconnect the A31 cooling fan ECU connector.


b.

Remove the FAN NO. 1 relay from the engine room relay block and 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
A31-1 (+B1) - 5 (FAN NO. 1 relay) Always Below 1 Ω


Standard Resistance (Check for Short):
Tester Connection Condition Specified Condition
A31-1 (+B1) or 5 (FAN NO. 1 relay) - Body ground Always 10 kΩ or higher



Result:
Proceed to
OK
NG



OK

10.CHECK HARNESS AND CONNECTOR (FAN NO. 1 RELAY - BODY GROUND)

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

10.CHECK HARNESS AND CONNECTOR (FAN NO. 1 RELAY - BODY GROUND)
a.

Remove the FAN NO. 1 relay from the engine room relay block and 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
2 (FAN NO. 1 relay) - Body ground Always Below 1 Ω



Result:
Proceed to
OK
NG



OK

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

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

11.CHECK HARNESS AND CONNECTOR (ECM - COOLING FAN ECU)
a.

Disconnect the A40 ECM connector.


b.

Disconnect the A31 cooling fan ECU connector.


c.

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

Standard Resistance (Check for Open):
Tester Connection Condition Specified Condition
A40-45 (RFC) - A31-2 (SI) Always Below 1 Ω



Result:
Proceed to
OK
NG



OK

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

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

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

Disconnect the z9 cooling fan motor connector.


b.

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

Standard Resistance (Check for Short):
Tester Connection Condition Specified Condition
z9-1 (-) - Body ground Always 10 kΩ or higher



Result:
Proceed to
OK
NG



OK

REPLACE COOLING FAN ECU

NG

REPLACE COOLING FAN MOTOR

Click hereEngine / Hybrid System>2ZR-FE COOLING>COOLING FAN MOTOR>REMOVAL