Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Diagnosis Procedure
- CHECK COOLING FAN CONTROL MODULE POWER SUPPLY CIRCUIT-I
- Turn ignition switch OFF.
- Disconnect cooling fan control module harness connectors E37, E38.
- Turn ignition switch ON.
- Check the voltage between cooling fan control module harness connector and ground.
Cooling fan control module Ground Voltage Connector Terminal E37 (Cooling fan control module 1) 3 Ground Battery voltage E38 (Cooling fan control module 2) 3 Is the inspection result normal?
YES: GO TO 2.
NO: GO TO 7.
- CHECK COOLING FAN CONTROL MODULE GROUND CIRCUIT
- Turn ignition switch OFF.
- Check the continuity between cooling fan control module harness connector and ground.
Cooling fan control module Ground Continuity Connector Terminal E37 (Cooling fan control module 1) 1 Ground Existed E38 (Cooling fan control module 2) 1 - Also check harness for short to power.
Is the inspection result normal?
YES: GO TO 3.
NO: Repair open circuit or short to power in harness or connectors.
- CHECK IPDM E/R GROUND CIRCUIT
- Disconnect IPDM E/R harness connectors E5, E6.
- Check the continuity between IPDM E/R harness connector and ground.
IPDM E/R Ground Continuity Connector Terminal E5 12 Ground Existed E6 41 - Also check harness for short to power.
Is the inspection result normal?
YES: GO TO 4.
NO: Repair open circuit or short to power in harness or connectors.
- CHECK COOLING FAN CONTROL SIGNAL CIRCUIT
- Disconnect IPDM E/R harness connector E9.
- Check the continuity between IPDM E/R harness connector and cooling fan control module harness connector.
IPDM E/R Cooling fan control module Continuity Connector Terminal Connector Terminal E9 97 E37 (Cooling fan control module 1) 2 Existed E38 (Cooling fan control module 2) 2 Existed - Also check harness for short to ground and short to power.
Is the inspection result normal?
YES: GO TO 5.
NO: Repair open circuit, short to ground or short to power in harness or connectors.
- CHECK COOLING FAN CONTROL MODULE OUTPUT SIGNAL CIRCUIT
- Reconnect all harness connectors disconnected.
- Disconnect cooling fan control module harness connectors E301, E303.
- Turn ignition switch ON.
- Check the voltage between cooling fan control module terminals and ground.
Cooling fan control module Ground Voltage Connector Terminal - (Cooling fan control module 1) 4 Ground Battery voltage - (Cooling fan control module 2) 6 Is the inspection result normal?
YES: GO TO 6.
NO: Replace malfunctioning cooling fan control module. Refer to "EXPLODED VIEW ".
- CHECK COOLING FAN MOTORS -1 AND -2
Refer to "COMPONENT INSPECTION (COOLING FAN MOTOR) ".
Is the inspection result normal?
YES: GO TO 11.
NO: Replace malfunctioning cooling fan motor. Refer to "EXPLODED VIEW ".
- CHECK COOLING FAN CONTROL MODULE POWER SUPPLY CIRCUIT-II
- Turn ignition switch OFF.
- Disconnect cooling fan relay-1 and cooling fan relay-2.
- Check the voltage between cooling fan relay harness connector and ground.
Cooling fan relay Ground Voltage Connector Terminal E15 (Cooling fan relay-1) 3 Ground Battery voltage E17 (Cooling fan relay-2) 3 - Turn ignition switch ON.
- Check the voltage between cooling fan relay harness connector and ground.
Cooling fan relay Ground Voltage Connector Terminal E15 (Cooling fan relay-1) 1 Ground Battery voltage Is the inspection result normal?
YES: GO TO 9.
NO: GO TO 8.
- DETECT MALFUNCTIONING PART
Check the following.
- 10 A fuse (No. 42)
- 50 A fusible link (letter O)
- 50 A fusible link (letter S)
- IPDM E/R harness connector E7
- Harness for open or short between cooling fan relay and fuse
- Harness for open or short between cooling fan relay and battery
: Repair open circuit, short to ground or short to power in harness or connectors.
- CHECK COOLING FAN CONTROL MODULE POWER SUPPLY CIRCUIT-III
- Turn ignition switch OFF.
- Disconnect IPDM E/R harness connector E6.
- Check the continuity between cooling fan relay harness connector and IPDM E/R harness connector.
Cooling fan relay IPDM E/R Continuity Connector Terminal Connector Terminal E15 (Cooling fan relay-1) 2 E6 42 Existed - Check the continuity between cooling fan relay harness connector and cooling fan control module harness connector.
Cooling fan relay Cooling fan control module Continuity Connector Terminal Connector Terminal E15 (Cooling fan relay-1) 5 E37 (Cooling fan control module-1) 3 Existed E17 (Cooling fan relay-2) 5 E38 (Cooling fan control module-2) 3 Existed - Check the continuity between cooling fan relay-1 harness connector and cooling fan relay-2 harness connector.
Cooling fan relay Continuity Connector Terminal Connector Terminal E15 (Cooling fan relay-1) 5 E17 (Cooling fan relay-2) 1 Existed - Check the continuity between cooling fan relay-2 harness connector and ground.
Cooling fan relay Ground Continuity Connector Terminal E17 (Cooling fan relay-1) 2 Ground Existed - Also check harness for short to ground and short to power.
Is the inspection result normal?
YES: GO TO 10.
NO: Repair open circuit, short to ground or short to power in harness or connectors.
- CHECK COOLING FAN RELAYS -1 AND -2
Refer to "COMPONENT INSPECTION (COOLING FAN RELAY) ".
Is the inspection result normal?
YES: GO TO 11.
NO: Replace malfunctioning cooling fan relay.
- CHECK INTERMITTENT INCIDENT
Perform "INTERMITTENT INCIDENT ".
Is the inspection result normal?
YES: Replace IPDM E/R. Refer to "REMOVAL AND INSTALLATION ".
NO: Repair or replace harness connectors.
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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