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 connector.
- Turn ignition switch ON.
- Check the voltage between cooling fan control module harness connector and ground.VOLTAGE REFERENCE
Cooling fan control module Ground Voltage Connector Terminal E37 3 Ground Battery voltage 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.CONTINUITY REFERENCE
Cooling fan control module Ground Continuity Connector Terminal E37 1 Ground Existed - 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.
- Check the continuity between IPDM E/R harness connector and ground.CONTINUITY REFERENCE
IPDM E/R Ground Continuity Connector Terminal E5 11 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.
- Check the continuity between IPDM E/R harness connector and cooling fan control module harness connector.CONTINUITY REFERENCE
IPDM E/R Cooling fan control module Continuity Connector Terminal Connector Terminal E9 97 E37 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.
- Turn ignition switch ON.
- Check the voltage between cooling fan control module harness connector and ground.VOLTAGE REFERENCE
Cooling fan control module Ground Voltage Connector Terminal E301 4 Ground Battery voltage E302 6 Is the inspection result normal?
YES: GO TO 6.
NO: Replace cooling fan control module.
- 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 cooling fan motor.
- CHECK COOLING FAN CONTROL MODULE POWER SUPPLY CIRCUIT-II
- Turn ignition switch OFF.
- Disconnect cooling fan relay.
- Turn ignition switch ON.
- Check the voltage between cooling fan relay harness connector and ground.VOLTAGE REFERENCE
Cooling fan relay Ground Voltage Connector Terminal E17 1 Ground Battery voltage 3 Is the inspection result normal?
YES: GO TO 9.
NO: GO TO 8.
- DETECT MALFUNCTIONING PART
Check the following.
- 10A fuse (No. 42)
- IPDM E/R harness connector E7
- 50A fusible link (letter O)
- 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.
- Check the continuity between cooling fan relay harness connector and IPDM E/R harness connector.CONTINUITY REFERENCE
Cooling fan relay IPDM E/R Continuity Connector Terminal Connector Terminal E17 2 E7 73 Existed - Check the continuity between cooling fan relay harness connector and cooling fan control module harness connector.CONTINUITY REFERENCE
Cooling fan relay Cooling fan control module Continuity Connector Terminal Connector Terminal E17 5 E37 3 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 RELAY
Refer to "COMPONENT INSPECTION (COOLING FAN RELAY) ".
Is the inspection result normal?
YES: GO TO 11.
NO: Replace cooling fan relay.
- CHECK INTERMITTENT INCIDENT
Perform "INTERMITTENT INCIDENT ".
Is the inspection result normal?
YES: Replace IPDM E/R.
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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