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.
CAUTION / NOTICE / HINT
Note
Inspect the fuses for circuits related to this system before performing the following procedure.
PROCEDURE
PERFORM ACTIVE TEST USING GTS (CONTROL THE ELECTRIC COOLING FAN)
Connect the GTS to the DLC3.
Turn the engine switch on (IG).
Turn the GTS on.
Enter the following menus: Powertrain / Engine / Active Test / Control the Electric Cooling Fan
| Tester Display |
|---|
| Control the Electric Cooling Fan |
Perform the Active Test according to the display on the GTS.
| OK | ||||||
|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| OK |
|
PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here |
| NG |
|
CHECK HARNESS AND CONNECTOR (FANL - FANH POWER SOURCE)
| *a | Front view of wire harness connector (to ECM) |
Disconnect the A53 ECM connector.
Turn the engine switch on (IG).
Measure the voltage according to the value(s) in the table below.
| Standard Voltage | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| NG |
|
INSPECT COOLING FAN RELAY (FAN NO. 1, FAN NO. 2 AND FAN NO. 3) Click here |
| OK |
|
CHECK HARNESS AND CONNECTOR (FAN NO. 1 RELAY AND FAN NO. 3 RELAY POWER SOURCE CIRCUIT)
| *1 | No. 2 Engine Room Relay Block |
| *2 | FAN NO. 1 relay |
| *3 | FAN NO. 3 relay |
Remove the FAN NO. 1 relay and FAN NO. 3 relay from the No. 2 engine room relay block.
Measure the voltage according to the value(s) in the table below.
| Standard Voltage | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR (FAN NO. 1 RELAY AND FAN NO. 3 RELAY POWER SOURCE CIRCUIT) |
| OK |
|
INSPECT COOLING FAN RELAY (FAN NO. 1, FAN NO. 2 AND FAN NO. 3)
Inspect the FAN NO. 1 relay, FAN NO. 2 relay and FAN NO. 3 relay.
| Result | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
|
| B |
|
REPLACE FAN NO. 1 RELAY |
| C |
|
REPLACE FAN NO. 2 RELAY |
| D |
|
REPLACE FAN NO. 3 RELAY |
| A |
|
CHECK HARNESS AND CONNECTOR (FAN NO. 2 RELAY - BODY GROUND)
| *1 | No. 2 Engine Room Relay Block |
| *2 | FAN NO. 2 relay |
Remove the FAN NO. 2 relay from the No. 2 engine room relay block.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance (Check for Open) | ||||||
|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR (FAN NO. 2 RELAY - BODY GROUND) |
| OK |
|
INSPECT COOLING FAN MOTOR
Inspect the cooling fan motor.
| Result | |||
|---|---|---|---|
|
| NG |
|
REPLACE COOLING FAN MOTOR Click here |
| OK |
|
CHECK HARNESS AND CONNECTOR (COOLING FAN MOTOR - BODY GROUND)
Disconnect the A7 cooling fan motor connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance (Check for Open) | ||||||
|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR (COOLING FAN MOTOR - BODY GROUND) |
| OK |
|
CHECK HARNESS AND CONNECTOR (COOLING FAN MOTOR - NO. 2 ENGINE ROOM RELAY BLOCK)
Disconnect the A7 cooling fan motor connector.
| *1 | No. 2 Engine Room Relay Block |
| *2 | FAN NO. 1 relay |
| *3 | FAN NO. 2 relay |
Remove the FAN NO. 1 relay and FAN NO. 2 relay from the No. 2 engine room relay block.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance (Check for Open) | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
| Standard Resistance (Check for Short) | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR (COOLING FAN MOTOR - NO. 2 ENGINE ROOM RELAY BLOCK) |
| OK |
|
INSPECT NO. 2 COOLING FAN MOTOR
Inspect the No. 2 cooling fan motor.
| Result | |||
|---|---|---|---|
|
| NG |
|
REPLACE NO. 2 COOLING FAN MOTOR Click here |
| OK |
|
CHECK HARNESS AND CONNECTOR (NO. 2 COOLING FAN MOTOR - NO. 2 ENGINE ROOM RELAY BLOCK)
Disconnect the A8 No. 2 cooling fan motor connector.
| *1 | No. 2 Engine Room Relay Block |
| *2 | FAN NO. 2 relay |
| *3 | FAN NO. 3 relay |
Remove the FAN NO. 2 relay and FAN NO. 3 relay from the No. 2 engine room relay block.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance (Check for Open) | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
| Standard Resistance (Check for Short) | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR (NO. 2 COOLING FAN MOTOR - NO. 2 ENGINE ROOM RELAY BLOCK) |
| OK |
|
CHECK HARNESS AND CONNECTOR (FAN NO. 1 RELAY - FAN NO. 2 RELAY)
| *1 | No. 2 Engine Room Relay Block |
| *2 | FAN NO. 1 relay |
| *3 | FAN NO. 2 relay |
Remove the FAN NO. 1 relay and FAN NO. 2 relay from the No. 2 engine room relay block.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance (Check for Open) | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
| Standard Resistance (Check for Short) | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| OK |
|
REPAIR OR REPLACE ECM Click here |
| NG |
|
REPAIR OR REPLACE NO. 2 ENGINE ROOM RELAY BLOCK |
INSPECT COOLING FAN RELAY (FAN NO. 1, FAN NO. 2 AND FAN NO. 3)
Inspect the FAN NO. 1 relay, FAN NO.2 relay and FAN NO.3 relay.
| Result | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
|
| B |
|
REPLACE FAN NO. 1 RELAY |
| C |
|
REPLACE FAN NO. 2 RELAY |
| D |
|
REPLACE FAN NO. 3 RELAY |
| A |
|
CHECK HARNESS AND CONNECTOR (NO. 2 ENGINE ROOM RELAY BLOCK - ECM)
| *1 | No. 2 Engine Room Relay Block |
| *2 | FAN NO. 1 relay |
| *3 | FAN NO. 2 relay |
| *4 | FAN NO. 3 relay |
Remove the FAN NO. 1 relay, FAN NO. 2 relay and FAN NO. 3 relay from the No. 2 engine room relay block.
Disconnect the A53 ECM connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance (Check for Open) | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
| Standard Resistance (Check for Short) | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| OK |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT) |
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR (NO. 2 ENGINE ROOM RELAY BLOCK - ECM) |