P0481-COOLING FAN 2 CONTROL CIRCUIT
For a complete wiring diagram Refer to Section 8W.
- When Monitored:
With the ignition on. Battery voltage greater than 10 volts.
- Set Condition:
The ECM receives a CAN Bus message from the TIPM indicating an open or shorted circuit on the Radiator Fan Medium/High Relay Control circuit.
| Possible Causes |
| FUSED B+ CIRCUITS |
| (N112) RADIATOR FAN RELAY CONTROL CIRCUIT OPEN |
| (N112) RADIATOR FAN RELAY CONTROL CIRCUIT SHORTED TO GROUND |
| RADIATOR FAN MEDIUM/HIGH RELAY |
| TOTALLY INTEGRATED POWER MODULE |
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).
Diagnostic Test
1. RADIATOR FAN MEDIUM/HIGH RELAY OPERATIONIgnition on, engine not running.
With a scan tool, select Radiator Cooling Fan Relay 2 Control State, to actuate the Radiator Fan Medium/High Relay.
Is the Cooling Fan Relay operating?
Yes
- Refer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)
- Perform the ECM Verification Test Ver. 1. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)
No
- Go To 2
2. FUSED B+ CIRCUITS
Turn the ignition off.
Remove the Radiator Medium/High Fan Relay.
Turn the ignition on.
Using a 12-volt test light connected to ground, probe the (A935) and (A16) Fused B+ circuits in the Relay connection.
Does the test light illuminate brightly?
Yes
- Go To 4
No
- Go To 3
3. RADIATOR FAN LOW/HIGH CONTROL RELAY SHORTED INTERNALLY
With the test light still at the Fused B+ circuits (Radiator Medium/High Fan Relay), remove the Radiator Fan Low/High Control Relay.
When the relay is removed, does the test light illuminate brightly?
Yes
- Replace the Radiator Fan Low/High Control Relay.
- Perform BODY VERIFICATION TEST – VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE)
No
- Repair the open or short to ground in the Fused B+ circuits. Inspect the related fuse and repair as necessary.
- Perform BODY VERIFICATION TEST – VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE)
4. (N112) RADIATOR FAN RELAY CONTROL CIRCUIT
Disconnect the TIPM C-11 harness connector.
Turn the ignition on, engine not running.
With a scan tool, select Radiator Cooling Fan Relay 2 Control State and then Toggle, to actuate the Radiator Fan Medium/High Relay.
Using a 12–volt test light connected to battery voltage, probe the (N112) Radiator Fan High Relay Control circuit in the TIPM C-11 harness connector.
Does the test light illuminate and flash on and off?
Yes
- Replace the Radiator Fan Medium/High Relay.
- Perform BODY VERIFICATION TEST – VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE)
No
- Go To 5
5. (N112) RADIATOR FAN RELAY CONTROL CIRCUIT OPEN
Turn the ignition off.
Measure the resistance of the (N112) Radiator Fan Relay Control circuit from the Relay connection to the TIPM C-11 harness connector.
Is the resistance below 10.0 ohms?
Yes
- Go To 6
No
- Replace the PDM in accordance with the Service Information.
- Perform BODY VERIFICATION TEST – VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE)
6. (N112) RADIATOR FAN RELAY CONTROL CIRCUIT SHORTED TO GROUND
Measure the resistance between ground and the (N112) Radiator Fan Relay Control circuit at the Relay connection.
Is the resistance below 100 ohms?
Yes
- Go To 7
No
- Replace the Totally Integrated Power Module in accordance with the Service Information.
- Perform BODY VERIFICATION TEST – VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE)
7. RADIATOR FAN LOW/HIGH CONTROL RELAY SHORTED INTERNALLY
With the probe still at the (N112) Radiator Fan Control circuit, remove the Radiator Fan Low/High Control Relay.
Is the resistance still below 10 ohms?
Yes
- Repair the open or short to ground in the (N112) Radiator Fan High Control circuit.
- Perform BODY VERIFICATION TEST – VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE)
No
- Replace the Radiator Fan Low/High Control Relay.
- Perform BODY VERIFICATION TEST – VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE)