Cooling Fan Circuit [10/2022 - 08/2023]: Procedure

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

   Powertrain > Engine > Active Test 

   Tester Display
   Control the Engine Cooling Fan Duty Ratio

   OK

   GTS Operation	Fan Operation
   30 - 100%	Cooling fan operates
   0%	Cooling fan stops

   Result

   Result	Proceed to
   OK	A
   Cooling fan does not operate	B
   Cooling fan does not stop	C

Result: 

A 

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE [10/2022 - ]  

Result: 

C 

See step  8

Result: 

B 

See step  2

1. Disconnect the A19 fan with motor assembly connector.
2. Disconnect the A15 ECM connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   A19-2 (SI) or A15-32 (RFC) - Body ground	Always	10 kΩ or higher

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR (FAN WITH MOTOR ASSEMBLY - ECM) 

Result: 

OK 

See step  3

1. Disconnect the A19 fan with motor assembly connector.
2. Operate the cooling fan motor (fan with motor assembly) using the Active Test function and measure the resistance according to the value(s) in the table below.

   Powertrain > Engine > Active Test 

   Tester Display
   Control the Engine Cooling Fan Duty Ratio

   Standard Resistance

   Tester Connection	GTS Operation	Specified Condition
   A19-2 (SI) - Body ground	Before Active Test (0%) → During Active Test (100%)	Before Active Test (0%): Resistance is stable → During Active Test (100%): Resistance fluctuates*

   HINT: 

   *: Using the Active Test, duty control of the transistors in the ECM will be performed. Due to the duty control, resistance of the RFC terminal will be unstable during the Active Test. If the resistance is stable before the Active Test and fluctuates while performing the Active Test, it can be determined that the transistor is operating. If the transistor does not operate during the Active Test, the ECM may be malfunctioning.

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPLACE ECM. Refer to  REMOVAL [10/2022 - 08/2023] 

Result: 

OK 

See step  4

1. Disconnect the A18 fan with motor assembly connector.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Front view of wire harness connector (to Fan with Motor Assembly)

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

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   A18-2 (+B1) - A18-1 (E1)	Always	11 to 14 V

   Result

   Proceed to
   OK
   NG

Result: 

NG 

See step  7

Result: 

OK 

See step  5

1. Disconnect the A19 fan with motor assembly connector.
2. Turn the ignition switch to ON.
3. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   A19-1 (IGS1) - Body ground	Ignition switch ON	11 to 14 V

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Front view of wire harness connector (to Fan with Motor Assembly)

   Result

   Proceed to
   OK
   NG

Result: 

OK 

REPLACE FAN WITH MOTOR ASSEMBLY. Refer to  REMOVAL [10/2022 - ] 

Result: 

NG 

See step  6

1. Disconnect the A19 fan with motor assembly connector.
2. Remove the EFI-MAIN NO. 1 relay from the No. 1 engine room relay block and No. 1 junction block assembly.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   A19-1 (IGS1) - 5 (EFI-MAIN NO. 1 relay)	Always	Below 1 Ω

   Result

   Result
   OK
   NG

Result: 

OK 

CHECK ECM POWER SOURCE CIRCUIT. Refer to  ECM Power Source Circuit [10/2022 - ] 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR (FAN WITH MOTOR ASSEMBLY - EFI-MAIN NO. 1 RELAY) 

1. Disconnect the A18 fan with motor assembly connector.
2. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   A18-1 (E1) - Body ground	Always	Below 1 Ω

   Result

   Result
   OK
   NG

Result: 

OK 

REPAIR OR REPLACE HARNESS OR CONNECTOR (FAN WITH MOTOR ASSEMBLY - AUXILIARY BATTERY) 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR (FAN WITH MOTOR ASSEMBLY - BODY GROUND) 

1. Disconnect the A19 fan with motor assembly connector.
2. Operate the cooling fan motor (fan with motor assembly) using the Active Test function and measure the resistance according to the value(s) in the table below.

   Powertrain > Engine > Active Test 

   Tester Display
   Control the Engine Cooling Fan Duty Ratio

   Standard Resistance

   Tester Connection	GTS Operation	Specified Condition
   A19-2 (SI) - Body ground	Before Active Test (0%) → During Active Test (100%)	Before Active Test (0%): Resistance is stable → During Active Test (100%): Resistance fluctuates*

   HINT: 

   *: Using the Active Test, duty control of the transistors in the ECM will be performed. Due to the duty control, resistance of the RFC terminal will be unstable during the Active Test. If the resistance is stable before the Active Test and fluctuates while performing the Active Test, it can be determined that the transistor is operating. If the transistor does not operate during the Active Test, the ECM may be malfunctioning.

   Result

   Proceed to
   OK
   NG

Result: 

OK 

REPLACE FAN WITH MOTOR ASSEMBLY. Refer to  REMOVAL [10/2022 - ] 

Result: 

NG 

See step  9

1. Disconnect the A19 fan with motor assembly connector.
2. Disconnect the A15 ECM connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   A19-2 (SI) - A15-32 (RFC)	Always	Below 1 Ω

   Result

   Result
   OK
   NG

Result: 

OK 

REPLACE ECM. Refer to  REMOVAL [10/2022 - 08/2023] 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR (FAN WITH MOTOR ASSEMBLY - ECM)