Radiator Cooling Fan: Testing and Inspection
CHECKING THE COOLING FAN OPERATION
For a complete wiring diagram refer to the Wiring Information .
1. LOW SPEED RADIATOR FAN CONTROL
NOTE: Diagnose and repair any Cooling Fan circuit or Temperature Sensor circuit DTCs before proceeding with this test.
1. Turn the ignition on.
2. With a scan tool, select Radiator Cooling Fan #1 Control State to actuate the Cooling Fan (Low Speed).
Does The Cooling Fan Operate?
Yes
- Go to 2
No
- Go To 3
2. HIGH SPEED RADIATOR FAN CONTROL
1. With a scan tool, select Radiator Cooling Fan #2 Control State to actuate the Cooling Fan (High Speed).
Does The Cooling Fan Operate?
Yes
- Test complete.
No
- Go to 4
3. LOW SPEED RAD FAN CONTROL CIRCUIT
1. Turn the ignition off.
2. Disconnect the Radiator Cooling Fan Module harness connector.
3. Turn the ignition on.
4. With a scan tool, select Radiator Cooling Fan #1 Control State, Toggle, to actuate the Cooling Fan (Low Speed).
5. Using a 12-volt test light connected to battery voltage, probe the (N201) Low Speed Rad Fan Control circuit in the Radiator Cooling Fan Module harness connector.
Does the test light illuminate brightly and flash on and off?
Yes
- Go To 5
No
- Go to 7
4. HIGH SPEED RAD FAN CONTROL CIRCUIT
1. Turn the ignition off.
2. Disconnect the Radiator Cooling Fan Module harness connector.
3. Turn the ignition on.
4. With a scan tool, select Radiator Cooling Fan #2 Control State, Toggle, to actuate the Cooling Fan (High Speed).
5. Using a 12-volt test light connected to battery voltage, probe the (N112) Low Speed Rad Fan Control circuit in the Radiator Cooling Fan Module harness connector.
Does the test light illuminate brightly and flash on and off?
Yes
- Go To 5
No
- Go to 10
5. (A16) FUSED B+ CIRCUIT
1. Turn the ignition off.
2. Using a 12-volt test light connected to ground, probe the (A16) Fused B+ circuit in the Radiator Cooling Fan Module harness connector.
Does the test light illuminate brightly?
Yes
- Go To 6
No
- Repair the (A16) Fused B+ circuit. Inspect the related fuse and repair as necessary.
- Perform the BODY VERIFICATION TEST - VER 1. Body Verification Test.
6. (Z903) GROUND CIRCUIT OPEN OR HIGH RESISTANCE
1. Using a 12 volt test light connected to 12 volts, check the (Z903) Ground circuit in the Radiator Cooling Fan Module harness connector.
NOTE: The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.
Is the test light illuminated and bright?
Yes
- Replace the Radiator Cooling Fan Module.
- Perform the BODY VERIFICATION TEST - VER 1. Body Verification Test.
No
- Repair the (Z903) Ground circuit for an open or high resistance.
- Perform the BODY VERIFICATION TEST - VER 1. Body Verification Test.
7. (N201) LOW SPEED RAD FAN CONTROL CIRCUIT SHORTED TO VOLTAGE
1. Turn the ignition off.
2. Disconnect the TIPM C11 harness connector.
3. Turn the ignition on.
4. Using a voltmeter, measure the voltage of the (N201) Low Speed Rad Fan Control circuit in the Radiator Cooling Fan Module harness connector.
Is there voltage present?
Yes
- Repair the (N201) Low Speed Rad Fan Control circuit for a short to voltage.
- Perform the BODY VERIFICATION TEST - VER 1. Body Verification Test.
No
- Go To 8
8. (N201) LOW SPEED RAD FAN CONTROL CIRCUIT OPEN
1. Turn the ignition off.
2. Measure the resistance of the (N201) Low Speed Rad Fan Control circuit from the Radiator Cooling Fan Module harness connector to the TIPM C11 harness connector.
Is the resistance below 5.0 ohms?
Yes
- Go To 9
No
- Repair the (N201) Low Speed Rad Fan Control circuit for an open or high resistance.
- Perform the BODY VERIFICATION TEST - VER 1. Body Verification Test.
9. (N201) LOW SPEED RAD FAN CONTROL CIRCUIT SHORTED TO GROUND
1. Measure the resistance between ground and the (N201) Low Speed Rad Fan Control circuit in the TIPM C11 harness connector.
Is the resistance below 100 ohms?
Yes
- Repair the (N201) Low Speed Rad Fan Control circuit for a short to ground.
- Perform the BODY VERIFICATION TEST - VER 1. Body Verification Test.
No
- Go to 13
10. (N112) HIGH SPEED RAD FAN CONTROL CIRCUIT SHORTED TO VOLTAGE
1. Turn the ignition off.
2. Disconnect the TIPM C11 harness connector.
3. Turn the ignition on.
4. Using a voltmeter, measure the voltage of the (N112) High Speed Rad Fan Control circuit in the Radiator Cooling Fan Module harness connector.
Is there voltage present?
Yes
- Repair the (N112) High Speed Rad Fan Control circuit for a short to voltage.
- Perform the BODY VERIFICATION TEST - VER 1. Body Verification Test.
No
- Go To 11
11. (N112) HIGH SPEED RAD FAN CONTROL CIRCUIT OPEN
1. Turn the ignition off.
2. Measure the resistance of the (N112) High Speed Rad Fan Control circuit from the Radiator Cooling Fan Module harness connector to the TIPM C11 harness connector.
Is the resistance below 5.0 ohms?
Yes
- Go To 12
No
- Repair the (N112) High Speed Rad Fan Control circuit for an open or high resistance.
- Perform the BODY VERIFICATION TEST - VER 1. Body Verification Test.
12. (N112) HIGH SPEED RAD FAN CONTROL CIRCUIT SHORTED TO GROUND
1. Measure the resistance between ground and the (N112) High Speed Rad Fan Control circuit in the TIPM C11 harness connector.
Is the resistance below 100 ohms?
Yes
- Repair the (N112) High Speed Rad Fan Control circuit for a short to ground.
- Perform the BODY VERIFICATION TEST - VER 1. Body Verification Test.
No
- Go to 13
13. TOTALLY INTEGRATED POWER MODULE (TIPM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Radiator Cooling Fan Module and the Totally Integrated Power Module (TIPM).
2. Look for any chafed, pierced, pinched, or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals.
4. Search for any Technical Service Bulletins that may apply.
Were any problems found?
Yes
- Repair as necessary.
- Perform the BODY VERIFICATION TEST - VER 1. Body Verification Test.
No
- Replace and program the Totally Integrated Power Module (TIPM).
- Perform the BODY VERIFICATION TEST - VER 1. Body Verification Test.