Symptom Diagnostic Procedures
SYSTEM DESCRIPTION
Input/output signal line
The ECM controls the cooling fan corresponding to vehicle speed, engine coolant temperature and air conditioner ON signal.
Operation
- The cooling fan operates at HIGH if diagnostic test mode II (self-diagnostic results) for engine coolant temperature sensor is "NG" or when the ECM fail-safe is activating.
- When A/C line pressure reaches the specified value, the triple-pressure switch turns on to operate cooling tans at low speed.
CONSULT-II REFERENCE VALUE IN DATA MONITOR MODE
Specification data are reference values.
ECM TERMINALS AND REFERENCE VALUE
Specification data are reference values, and are measured between each terminal and (128) (ECM ground).
CONSULT-II REFERENCE VALUE IN DATA MONITOR MODE
Specification data are reference values.
ON BOARD DIAGNOSIS LOGIC
This diagnosis continuously monitors the engine coolant temperature.
If the cooling fan or another component in the cooling system malfunctions, the engine coolant temperature will rise.
When the engine coolant temperature reaches an abnormally high temperature condition, a malfunction is indicated.
CAUTION: When a malfunction is indicated, be sure to replace the coolant following the procedure in "Changing Engine Coolant", "ENGINE MAINTENANCE". Also, replace the engine oil.
a. Fill radiator with coolant up to specified level with a filling speed of 2 liters per minute like pouring coolant by kettle. Be sure to use coolant with the proper mixture ratio. Refer to "Anti-freeze Coolant Mixture Ratio", "RECOMMENDED FLUIDS AND LUBRICANTS".
b. After refilling coolant, run engine to ensure that no water-flow noise is emitted.
OVERALL FUNCTION CHECK
Use this procedure to check the overall function of the cooling fan. During this check, a 1St trip DTC might not be confirmed.
WARNING: Never remove the radiator cap when the engine is hot. Serious burns could be caused by high pressure fluid escaping from the radiator.
Wrap a thick cloth around cap. Carefully remove the cap by turning it a quarter turn to allow built-up pressure to escape. Then turn the cap all the way off.
1. Check the coolant level in the reservoir tank and radiator.
Allow engine to cool before checking coolant level.
If the coolant level in the reservoir tank and/or radiator is below the proper range, skip the following steps and go to "DIAGNOSTIC PROCEDURE".
2. Confirm whether customer filled the coolant or not. If customer filled the coolant, skip the following steps and go to "DIAGNOSTIC PROCEDURE".
With Consult
3. Turn ignition switch "ON".
4. Perform "COOLING FAN" in "ACTIVE TEST" mode with CONSULT-II.
5. If NG, go to "DIAGNOSTIC PROCEDURE".
OR
Without Consult
3. Disconnect engine coolant temperature sensor harness connector.
4. Connect 150 Ohms resistor to engine coolant temperature sensor harness connector.
5. Start engine and make sure that cooling fan operates.
Be careful not to overheat engine.
6. If NG, go to "DIAGNOSTIC PROCEDURE".
EC-COOL/F-01:
EC-COOL/F-01 - Connector View:
WIRING DIAGRAM
M1 Connector View:
Part 1 Of 2:
Part 2 Of 2:
DIAGNOSTIC PROCEDURE
Part 1 Of 2:
Part 2 Of 2:
PROCEDURE A
Part 1 Of 3:
Part 2 Of 3:
Part 3 Of 3:
PROCEDURE B
Perform FINAL CHECK by the following procedure after repair is completed.
1. Warn up engine. Run the vehicle for at least 20 minutes. Pay attention to engine coolant temperature gauge on the instrument panel. If the reading shows an abnormally high temperature, another part may be malfunctioning.
2. Stop vehicle and let engine idle. Check the intake and exhaust Systems for leaks by listening for noise or visually inspecting the components.
3. Allow engine to cool and visually check for oil and coolant leaks. Then, perform "OVERALL FUNCTION CHECK".
MAIN 12 CAUSES OF OVERHEATING:
COMPONENT INSPECTION
Cooling fan relays-1 and -2, -3
Check continuity between terminals (3) and (5), (6) and (7)
Cooling fan motor
1. Disconnect cooling fan motor harness connectors.
2. Supply cooling fan motor terminals with battery voltage and check operation as shown in the figure.
If NG, replace cooling fan motor.