M20C-FKS, M20D-FKS 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 status, refrigerant pressure, engine speed and vehicle speed, and sends a signal to the cooling fan ECU (fan with motor assembly). The cooling fan ECU (fan with motor assembly) steplessly control the speed of the cooling fan based on the duty cycle signal sent from the ECM. By sending signals to the cooling fan ECU (fan with motor assembly) in accordance with the driving conditions and by controlling the cooling fan speed optimally with the ECM, both high cooling performance and quietness are ensured.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
- NOTICE:
- ·
Inspect the fuses for circuits related to this system before performing the following procedure.
·Make sure to perform the necessary procedures (adjustment, calibration, initialization, or registration) after parts related to the cooling fan system have been removed/installed or replaced.
PROCEDURE
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 - 50004 372 11
- 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
A
B
C
Disconnect the A30 fan with motor assembly connector.
Disconnect the A28 ECM connector.
Measure the resistance according to the value(s) in the table below.
- Standard Resistance:
Tester Connection Condition Specified Condition Click Location & Routing(A30,A28)Location & Routingewd_type=routing;type=c,c;code=A30,A28
Click Connector(A30)Engine Compartment>Engine Room Main Wire / Transmission Wire>Fan with Motor Assemblyewd_type=component;type=c;code=A30;pinno=3
Click Connector(A28)Engine Compartment>Engine Room Main Wire / Transmission Wire>ECMewd_type=component;type=c;code=A28;pinno=32
A30-3 (SI) or A28-32 (RFC) - Body ground Always 10 kΩ or higher
- Result:
Proceed to OK NG
OK
NG
Disconnect the A30 fan with motor assembly connector.
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 - 50004 372 11
- Standard Resistance:
Tester Connection GTS Operation Specified Condition Click Location & Routing(A30)Location & Routingewd_type=routing;type=c;code=A30
Click Connector(A30)Engine Compartment>Engine Room Main Wire / Transmission Wire>Fan with Motor Assemblyewd_type=component;type=c;code=A30;pinno=3
A30-3 (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
OK
NG
Disconnect the A30 fan with motor assembly connector.
Measure the voltage according to the value(s) in the table below.
- Standard Voltage:
Tester Connection Condition Specified Condition Click Location & Routing(A30)Location & Routingewd_type=routing;type=c;code=A30
Click Connector(A30)Engine Compartment>Engine Room Main Wire / Transmission Wire>Fan with Motor Assemblyewd_type=component;type=c;code=A30;pinno=1,2
A30-1 (+B1) - A30-2 (E1) Always 11 to 14 V
- Result:
Proceed to OK NG
OK
NG
Disconnect the A30 fan with motor assembly connector.
Turn the ignition switch to ON.
Measure the voltage according to the value(s) in the table below.
- Standard Voltage:
Tester Connection Condition Specified Condition Click Location & Routing(A30)Location & Routingewd_type=routing;type=c;code=A30
Click Connector(A30)Engine Compartment>Engine Room Main Wire / Transmission Wire>Fan with Motor Assemblyewd_type=component;type=c;code=A30;pinno=4,2
A30-4 (IGS1) - A30-2 (E1) Ignition switch ON 11 to 14 V
- Result:
Proceed to OK NG
OK
NG
Disconnect the A30 fan with motor assembly connector.
Remove the EFI-MAIN NO. 1 relay from the No. 1 engine room relay block and No. 1 junction block assembly.
Measure the resistance according to the value(s) in the table below.
- Standard Resistance:
Tester Connection Condition Specified Condition Click Location & Routing(A30)Location & Routingewd_type=routing;type=c;code=A30
Click Connector(A30)Engine Compartment>Engine Room Main Wire / Transmission Wire>Fan with Motor Assemblyewd_type=component;type=c;code=A30;pinno=4
A30-4 (IGS1) - 5 (EFI-MAIN NO. 1 relay) Always Below 1 Ω
- Result:
Result OK NG
OK
NG
Disconnect the A30 fan with motor assembly connector.
Measure the resistance according to the value(s) in the table below.
- Standard Resistance:
Tester Connection Condition Specified Condition Click Location & Routing(A30)Location & Routingewd_type=routing;type=c;code=A30
Click Connector(A30)Engine Compartment>Engine Room Main Wire / Transmission Wire>Fan with Motor Assemblyewd_type=component;type=c;code=A30;pinno=2
A30-2 (E1) - Body ground Always Below 1 Ω
- Result:
Proceed to OK NG
OK
NG
Disconnect the A30 fan with motor assembly connector.
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 - 50004 372 11
- Standard Resistance:
Tester Connection GTS Operation Specified Condition Click Location & Routing(A30)Location & Routingewd_type=routing;type=c;code=A30
Click Connector(A30)Engine Compartment>Engine Room Main Wire / Transmission Wire>Fan with Motor Assemblyewd_type=component;type=c;code=A30;pinno=3
A30-3 (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
OK
NG
Disconnect the A30 fan with motor assembly connector.
Disconnect the A28 ECM connector.
Measure the resistance according to the value(s) in the table below.
- Standard Resistance:
Tester Connection Condition Specified Condition Click Location & Routing(A30,A28)Location & Routingewd_type=routing;type=c,c;code=A30,A28
Click Connector(A30)Engine Compartment>Engine Room Main Wire / Transmission Wire>Fan with Motor Assemblyewd_type=component;type=c;code=A30;pinno=3
Click Connector(A28)Engine Compartment>Engine Room Main Wire / Transmission Wire>ECMewd_type=component;type=c;code=A28;pinno=32
A30-3 (SI) - A28-32 (RFC) Always Below 1 Ω
- Result:
Result OK NG
OK
NG