Cooling Fan Motor Operation Inspection
1. Verify that the battery voltage is above 12.4 V.
• If the battery voltage is below 12.4 V, charge the battery or connect the external power supply.
2. Connect the WDS or equivalent to the DLC-2.
3. Access the following PIDs.
• ECT
• AC_REQ
• COLP
4. Turn the A/C switch to off.
5. Verify that ECT PID is below 98 °C {209 °F} and the AC_REQ is off.
• If the ECT PID is below 98 °C {209 °F}, inspect the ECT sensor.
• If the AC_REQ PID is on, inspect the A/C switch and A/C refrigerant pressure switch (high/low pressure).
6. Turn the ignition switch to the ON position while the temperature is below 98 °C {209 °F} with the ignition switch in the ON position.
7. Verify that the cooling fan is not operating.
• If the cooling fan is operating inspect the following:
(1) Verify that the FAN DUTY PID is 0 %.
• If the FAN DUTY PID is not 0 %, inspect the following PID and related parts.
- ECT (ECT sensor)
- AC_REQ (A/C switch and A/C refrigerant pressure switch (high/low) pressure)
- COLP (A/C refrigerant pressure switch (medium pressure))
- VSS (Vehicle speed sensor)
- ACCS (A/C magnetic clutch)
• If the FAN DUTY PID is 0 %, replace cooling fan component.
8. Turn the A/C switch to on.
9. Verify that the cooling fan is operating while the ECT PID is below 98 °C {209 °F}.
• If the cooling fan does not operate, inspect for the following:
- A/C switch
- A/C refrigerant pressure switch
- Fan control module power supply circuit (open or short circuit)
- Fan control module GND circuit (open or short circuit)
- Fan control module control signal circuit (open or short circuit between fan control module terminal B and PCM terminal 1AP)
- Fan control module
(See COOLING FAN MOTOR COMPONENT INSPECTION.)
10. Verify that the cooling fan operates at medium speed while the COLP PID is off and high speed while the COLP PID is on.
• If the cooling fan does not operate medium and/or high speed, inspect for the following:
- A/C refrigerant pressure switch (medium switch)
- Fan control module
(See COOLING FAN MOTOR COMPONENT INSPECTION.)
11. Turn the A/C switch to the off position.
12. Start the engine and idle it.
13. Verify that the cooling fan operating speed increases relative to the ECT PID increase.
• If the cooling fan speed does not increase inspect the following:
- ECT sensor (characteristic)
- Fan control signal circuit (between fan control module terminal B and PCM terminal 1AP)
• If the all items are normal, replace the cooling fan component.
