P0480
P0480 - Cooling Fan 1 Control Circuit
For wiring diagrams, refer to.
• When Monitored: With the engine running, battery voltage greater than 10.4 volts, and the cooling fan 1 control active.
• Set Condition: The PCM detects an open or shorted condition in the cooling fan 1 control circuit.
• Always perform the pre-diagnostic troubleshooting procedure before proceeding. Refer to => Non-DTC Based Diagnostics. Pre-Diagnostic Troubleshooting Procedure
Test Step 1 - DTC is Active
• Turn the ignition ON.
• With the scan tool, actuate the cooling fan 1 control.
• With the scan tool, select view DTCs.
Is the status active for this DTC?
Yes
• Go to Test Step 2 => [ Test
Step 2 - Fused B+ Circuits Open or High Resistance ]
No
• Refer to the checking for an intermittent DTC diagnostic procedure. Refer to => Non-DTC Based Diagnostics. Checking for an Intermittent DTC
Test Step 2 - Fused B+ Circuits Open or High Resistance
• Turn the ignition OFF.
• Remove the radiator fan low speed relay from the TIPM.
• Turn the ignition ON.
• Using a test lamp connected to ground, check the fused B+ circuits in the radiator fan low speed relay connector.
• The test lamp should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.
Is the test lamp illuminated and bright?
Yes
• Go to Test Step 3 => [ Test
Step 3 - Cooling Fan 1 Control Actuation ]
No
• Repair the fused B+ circuits for an open circuit or high resistance.
• Perform the PCM Verification Test. Refer to => Non-DTC
Based Diagnostics. PCM Verification Test
Test Step 3 - Cooling Fan 1 Control Actuation
• Turn the ignition OFF.
• Remove the cooling fan low speed relay from the TIPM.
• Turn the ignition ON.
• With the scan tool, actuate the cooling fan 1 control to ON.
• Using a test lamp connected to ground, check the radiator fan low speed control circuit in the radiator fan resistor harness connector.
• The test lamp should be illuminated and bright proportional to the maximum duty cycle allowed by the scan tool. For example, if the scan tool allows 100% actuation, the brightness should be as bright as a direct connection to the battery. If the scan tool allows a maximum 25% actuation, the brightness should be 25% as bright as a direct connection to the battery.
• With the scan tool, actuate the radiator fan resistor control to OFF.
• Using a test lamp connected to ground, check the radiator fan low speed control circuit in the radiator fan resistor harness connector.
• The test lamp should not be illuminated with the control actuated OFF (0%).
Is the test lamp illuminated when actuated ON and not illuminated when actuated OFF as described?
Yes
• Go to Test Step 4 => [ Test
Step 4 - Radiator Fan Low Speed Relay ]
No
• Go to Test Step 5 => [ Test
Step 5 - Totally Integrated Power Module ]
Test Step 4 - Radiator Fan Low Speed Relay
• Turn the ignition OFF.
• Inspect the connectors where the radiator fan low speed relay connects to the totally integrated power module.
• Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the related connectors.
Were any problems found?
Yes
• Repair as necessary.
• Perform the PCM Verification Test. Refer to => Non-DTC
Based Diagnostics. PCM Verification Test
No
• Replace the radiator fan low speed relay.
• Perform the PCM Verification Test. Refer to => Non-DTC
Based Diagnostics. PCM Verification Test
Test Step 5 - Totally Integrated Power Module
• Inspect the connectors where the radiator fan low speed relay connects to the totally integrated power module.
• Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the related connectors.
• Refer to any technical service bulletins that may apply.
Were any problems found?
Yes
• Repair as necessary.
• Perform the PCM Verification Test. Refer to => Non-DTC
Based Diagnostics. PCM Verification Test
No
• Replace and program the totally integrated power module.
• Perform the PCM Verification Test. Refer to => Non-DTC
Based Diagnostics. PCM Verification Test