Diagnostic Test
- RADIATOR FAN MEDIUM/HIGH RELAY NOTE:
Diagnose and repair any Coolant Fan circuit or Temperature Sensor circuit DTCs before proceeding with this test.
- RADIATOR FAN LOW/HIGH RELAY
- With the scan tool, actuate the Radiator Fan 1 Control State.
Do both Cooling Fans Operate?
Yes
- Test complete.
No
- Go To 3
- With the scan tool, actuate the Radiator Fan 1 Control State.
- (N23) LOW/HIGH RAD FAN RELAY OUTPUT CIRCUIT
- Turn the ignition off.
- Disconnect the C1 Radiator Cooling Fan Module harness connector.
- Turn the ignition on.
- Using a 12-volt test light connected to ground, check the (N23) Low/High Rad Fan Relay Output circuit in the C1 Radiator Cooling Fan Module harness connector.
- With the scan tool, actuate the Radiator Fan 1 Control State.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
- Go To 6
No
- Go To 4
- RADIATOR FAN LOW/HIGH RELAY
- Turn the ignition off.
- Verify the Radiator Fan Low/High Relay is installed properly and the terminals are making a tight fit.
- Remove the Radiator Fan Low/High Relay and substitute it with a known good Relay.
- Turn the ignition on.
- Using a 12-volt test light connected to ground, check the (N23) Low/High Rad Fan Relay Output circuit in the C1 Radiator Cooling Fan Module harness connector.
- With the scan tool, actuate the Radiator Fan 1 Control State.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 Fan Low/High Relay.
- Perform the PCM VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
No
- Go To 5
- (N23) LOW/HIGH RAD FAN RELAY OUTPUT CIRCUIT OPEN OR HIGH RESISTANCE
- Measure the resistance of the (N23) Low/High Rad Fan Relay Output circuit between the C1 Radiator Cooling Fan Module harness connector and the Radiator Fan Low/High Relay.
Is the resistance above 5.0 Ohms?
Yes
- Repair the (N23) Low/High Rad Fan Relay Output circuit for an open or high resistance.
- Perform the PCM VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
No
- Go To 17
- Measure the resistance of the (N23) Low/High Rad Fan Relay Output circuit between the C1 Radiator Cooling Fan Module harness connector and the Radiator Fan Low/High Relay.
- (N210) RADIATOR FAN SERIES/PARALLEL RELAY
- Turn the ignition off.
- Connect the C1 Radiator Cooling Fan Module harness connector.
- Remove the Radiator Fan Series/Parallel Relay.
- Turn the ignition on.
- Using a 12-volt test light connected to ground, check the (N210) Series/Parallel Rad Fan Relay Feed circuit in the Radiator Fan Series/Parallel Relay harness connector.
- With the scan tool, actuate the Radiator Fan 1 Control State.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
- Go To 8
No
- Go To 7
- COOLING FAN
- Turn the ignition off.
- Disconnect the C1 Radiator Cooling Fan Module harness connector.
- Connect a jumper wire between the (N23) Low/High Rad Fan Relay Output circuit and the (N210) Series/Parallel Rad Fan Relay Feed of the C1 Radiator Cooling Fan Module harness connector.
- Turn the ignition on.
- Using a 12-volt test light connected to ground, check the (N210) Series/Parallel Rad Fan Relay Feed circuit in the Radiator Fan Series/Parallel Relay harness connector.
- With the scan tool, actuate the Radiator Fan 1 Control State.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 Cooling Fan.
- Perform the PCM VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
No
- Go To 9NOTE:
Remove the jumper wire before continuing.
- RADIATOR FAN SERIES/PARALLEL RELAY
- Turn the ignition off.
- Verify the Radiator Fan Series/Parallel Relay is installed properly and the terminals are making a tight fit.
- Remove the Radiator Fan Series/Parallel Relay and substitute it with a known good Relay.
- Turn the ignition on.
- With the scan tool, actuate the Radiator Fan 1 Control State.
Do Both Cooling Fans Operate?
Yes
- Replace the Radiator Fan Series/Parallel Relay.
- Perform the PCM VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
No
- Go To 17
- (N210) RAD FAN HIGH/LOW CONTROL FEED SHORT TO GROUND
- Turn the ignition off.
- Measure the resistance between ground and the (N210) Rad Fan High/Low Relay Feed circuit in the C1 Radiator Cooling Fan Module harness connector.
Is the resistance below 100 Ohms?
Yes
- Repair the (N210) Rad Fan High/Low Control Feed circuit for a short to ground.
- Perform the PCM VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
No
- Go To 10
- (N210) RAD FAN HIGH/LOW CONTROL FEED OPEN OR HIGH RESISTANCE
- Measure the resistance of the (N210) Rad Fan High/Low Control Feed circuit between the C1 Radiator Cooling Fan Module harness connector and the Radiator Fan Series/Parallel Relay.
Is the resistance above 5.0 Ohms?
Yes
- Repair the (N210) Rad Fan High/Low Control Feed circuit for an open or high resistance.
- Perform the PCM VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
No
- Go To 17
- Measure the resistance of the (N210) Rad Fan High/Low Control Feed circuit between the C1 Radiator Cooling Fan Module harness connector and the Radiator Fan Series/Parallel Relay.
- (Z902) GROUND CIRCUIT OPEN
- Turn the ignition off.
- Disconnect the C2 Radiator Cooling Fan Module harness connector.
- Using a 12-volt test light connected to voltage, check the (Z902) Ground circuit in the C2 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
- Go To 12
No
- Repair the (Z902) Ground circuit for an open or high resistance.
- Perform the PCM VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
- (N24) RAD FAN RELAY OUTPUT CIRCUIT
- Turn the ignition on.
- Using a 12-volt test light connected to ground, check the (N24) Rad Fan Relay Output circuit in the C2 Radiator Cooling Fan Module harness connector.
- With the scan tool, actuate the Radiator Fan 2 Control State.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 Cooling Fan.
- Perform the PCM VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
No
- Go To 13
- RADIATOR FAN MEDIUM/HIGH RELAY
- Turn the ignition off.
- Verify the Radiator Fan Medium/High Relay is installed properly and the terminals are making a tight fit.
- Remove the Radiator Fan Medium/High Relay and substitute it with a known good Relay.
- Turn the ignition on.
- Using a 12-volt test light connected to ground, check the (N24) Rad Fan Relay Output circuit in the C2 Radiator Cooling Fan Module harness connector.
- With the scan tool, actuate the Radiator Fan 2 Control State.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 Fan Medium/High Relay.
- Perform the PCM VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
No
- Go To 14
- (A16) FUSED B+ CIRCUIT
- Turn the ignition off.
- Remove the Radiator Fan Medium/High Relay.
- Turn the ignition on.
- Using a 12-volt test light connected to ground, check the (A16) Fused B+ circuit in the Radiator Fan Medium/High Relay 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
- Go To 16
No
- Go To 15
- (A16) FUSED B+ CIRCUIT OPEN OR SHORT TO GROUND
- Turn the ignition off.
- Inspect the (A16) Fused B+ fuse.
Is the fuse open?
Yes
- Repair the (A16) B+ circuit, the (N23) Low/High Rad Fan Relay Output circuit or the (N24) Rad Fan Medium/High Relay Output circuit for a short to ground.
- Replace the (A16) Fused B+ fuse.
- Perform the PCM VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
No
- Repair the (A16) Fused B+ circuit for an open.
- Perform the PCM VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
- (N24) RAD FAN RELAY OUTPUT CIRCUIT OPEN OR HIGH RESISTANCE
- Measure the resistance of the (N24) Rad Fan Relay Output circuit between the C2 Radiator Cooling Fan Module harness connector and the Radiator Fan Medium/High Relay harness connector.
Is the resistance above 5.0 Ohms?
Yes
- Repair the (N24) Rad Fan Relay Output circuit for an open or high resistance.
- Perform the PCM VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
No
- Go To 17
- Measure the resistance of the (N24) Rad Fan Relay Output circuit between the C2 Radiator Cooling Fan Module harness connector and the Radiator Fan Medium/High Relay harness connector.
- RELAY BLOCK NOTE:
Before continuing, check the connector terminals for corrosion, damage, or terminal push out. Repair as necessary.
- Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and Ground circuits.
Were there any problems found?
Yes
- Repair as necessary.
- Perform the PCM VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
No
- Replace the Relay Block in accordance with the Service Information.
- Perform the PCM VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
- Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and Ground circuits.