TEST
ACTION
APPLICABILITY
3
Turn the ignition off.
Disconnect the Radiator Fan Relay harness connector.
Using a 12-volt test light connected to 12-volts, probe the Ground circuit in the
Radiator Fan Relay harness connector.
Does the test light illuminate?
All
Yes
→ Go To 4
No
→ Repair the Ground circuit for an open.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
4
NOTE: Inspect the Radiator Fan fuse located in the IPM.
Turn the ignition off.
Disconnect the Radiator Fan Relay harness connector.
Measure the voltage of the Fused B+ Output circuit in the Radiator Fan harness
connector.
Is the voltage above 11.0 volts?
All
Yes
→ Go To 5
No
→ Repair the Fused B+ circuit. Check and replace any open fuses.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
5
NOTE: Ensure the Radiator Fan Relay harness connector is connected.
Turn the ignition off.
Disconnect the PCM harness connector.
Turn the ignition on.
CAUTION: DO NOT PROBE THE PCM HARNESS CONNECTORS. PROBING
THE PCM HARNESS CONNECTORS WILL DAMAGE THE PCM TERMI-
NALS RESULTING IN POOR TERMINAL TO PIN CONNECTION. INSTALL
MILLER SPECIAL TOOL #8815 TO PERFORM DIAGNOSIS.
Using a jumper wire, momentarily jumper the Radiator Fan Relay Control circuit in
the appropriate terminal of special tool # 8815 to ground.
Did the Radiator Fans operate?
All
Yes
→ Before continuing, check the PCM harness connector terminals
for corrosion, damage, or terminal push out. Repair as necessary.
Replace and program the Powertrain Control Module in accor-
dance with the Service Information.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No
→ Go To 6
6
Turn the ignition off.
Disconnect the Radiator Fan Relay harness connector.
Disconnect the PCM harness connector.
CAUTION: DO NOT PROBE THE PCM HARNESS CONNECTORS. PROBING
THE PCM HARNESS CONNECTORS WILL DAMAGE THE PCM TERMI-
NALS RESULTING IN POOR TERMINAL TO PIN CONNECTION. INSTALL
MILLER SPECIAL TOOL #8815 TO PERFORM DIAGNOSIS.
Measure the resistance of the Radiator Fan Relay Control circuit between the
Radiator Fan Relay harness connector and the appropriate terminal of special tool #
8815.
Is the resistance below 5.0 ohms?
All
Yes
→ Go To 7
No
→ Go To 10
376
DRIVEABILITY - NGC
P0480-LOW SPEED FAN CONTROL RELAY CIRCUIT —
Continued