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For 1990-2009 cars only

Cooling Fan Inoperative L61

Step

Action

Yes

No

Schematic Reference: Engine Cooling Schematics

Connector End View Reference: Cooling System Connector End Views

DEFINITION: The cooling fan motor is inoperative in either high or low speeds.

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. With a scan tool, command the Fan Control 1 ON and OFF.

Does the cooling fan turn ON and OFF in low speed with each command?

Go to Step 3

Go to Step 4

3

Important: A 3 second delay occurs before the engine control module (ECM)/powertrain control module (PCM) changes the cooling fan speed.

With a scan tool, command the Fan Control 2 Speed ON and OFF.

Does the cooling fan turn ON and OFF in high speed with each command?

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 6

4

    Important: Do NOT remove the jumper wire that you will be connecting until your testing is completed. If the low speed fan fuse opens when you connect the jumper wire, repair the cooling fan motor supply voltage circuit of the cooling fan motor for a short to ground.

  1. Disconnect the cool fan low relay.
  2. Connect a jumper wire between the battery positive voltage circuit and the cooling fan motor supply voltage circuit of the low speed fan relay.

Does the cooling fan operate in low speed?

Go to Step 11

Go to Step 5

5

  1. Disconnect the cool fan high relay.
  2. With a test lamp connected to a good ground, probe the cooling fan low reference circuit at the cooling fan resistor.

Does the test lamp illuminate?

Go to Step 9

Go to Step 8

6

Does the cooling fan operate at high speed?

Go to Step 12

Go to Step 7

7

Inspect the ground circuit of the cool fan high relay for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 18

Go to Step 12

8

  1. Install the cool fan high relay.
  2. Disconnect the cooling fan electrical connector.
  3. With a test lamp connected to a good ground, probe the cooling fan motor supply voltage circuit at the cooling fan motor connector.

Does the test lamp illuminate?

Go to Step 10

Go to Step 9

9

Inspect the cooling fan motor supply voltage circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 18

Go to Step 14

10

Inspect the ground circuit of the cooling fan for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 18

Go to Step 13

11

Inspect for poor connections at the cool fan low relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 18

Go to Step 15

12

Inspect for poor connections at the cool fan high relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 18

Go to Step 13

13

Inspect for poor connections at the harness connector of the cooling fan. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 18

Go to Step 17

14

Inspect the battery positive voltage circuit for an open or high resistance. Refer to Wiring Repairs and Circuit Testing in Wiring Systems.

Did you find and correct the condition?

Go to Step 18

Go to Step 16

15

Replace the cool fan low relay.

Did you complete the replacement?

Go to Step 18

--

16

Replace the cool fan high relay.

Did you complete the replacement?

Go to Step 18

--

17

Replace the cooling fan. Refer to Cooling Fan and Shroud Replacement .

Did you complete the replacement?

Go to Step 18

--

18

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3

Cooling Fan Inoperative L66

Step

Action

Yes

No

Schematic Reference: Engine Cooling Schematics

Connector End View Reference: Cooling System Connector End Views

DEFINITION: One or both cooling fan motors are inoperative in either high, low, or both speeds.

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

Test cool fan 1, cool fan 2 and cool fan 3 relay control circuits for an open.

Did you find and correct the condition?

Go to Step 29

Go to Step 3

3

  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. With a scan tool, command the Fans Control 1 ON and OFF.

Do the low speed engine cooling fans turn ON and OFF with each command?

Go to Step 4

Go to Step 5

4

Important:: A 3 second delay occurs before the powertrain control module (PCM) changes the cooling fan speed.

With a scan tool, command the Fans Control 2 and 3 ON and OFF.

Do the high speed engine cooling fans turn ON and OFF with each command?

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 12

5

    Important: Do NOT remove the 20-amp fused jumper wire connected during this step. Use a second 20-amp fused jumper wire while performing the following steps.

  1. Disconnect the cooling fan 1 relay.
  2. Connect the first 20-amp fused jumper between the battery positive voltage circuit of the cooling fan 1 relay and the cooling fan motor supply voltage circuit of the cooling fan 1 relay.

Do both cooling fans operate in low speed?

Go to Step 14

Go to Step 6

6

  1. Disconnect the cooling fan 3 relay
  2. Connect the second 20-amp fused jumper between the left cooling fan motor low reference circuit of the cooling fan 2 relay and the right cooling fan motor supply voltage circuit of the cooling fan 2 relay.

Do both cooling fans operate in low speed?

Go to Step 15

Go to Step 7

7

Reconnect the second 20-amp fused jumper between the battery positive voltage circuit of the cooling fan 2 relay and the cooling fan motor supply voltage circuit of the cooling fan 2 relay.

Does the right cooling fan operate in high speed?

Go to Step 10

Go to Step 8

8

  1. Install the cooling fan 2 relay.
  2. Disconnect the right cooling fan electrical connector.
  3. Reconnect the second 20-amp fused jumper wire from the cooling fan motor supply voltage circuit of the right cooling fan electrical connector to the cooling fan motor ground circuit of the right cooling fan electrical connector.

Does the left cooling fan operate in high speed?

Go to Step 17

Go to Step 9

9

Reconnect the second 20-amp fused jumper wire from the cooling fan motor supply voltage circuit of the right cooling fan electrical connector to a good ground.

Does the left cooling fan operate in high speed?

Go to Step 21

Go to Step 22

10

  1. Install the cooling fan 2 relay.
  2. Disconnect the left cooling fan electrical connector.
  3. Reconnect the second 20-amp fused jumper wire from cooling fan motor supply voltage circuit of the left cooling fan electrical connector to the cooling fan low reference circuit of the left cooling fan electrical connector.

Does the right cooling fan operate in high speed?

Go to Step 18

Go to Step 11

11

Reconnect the second 20-amp fused jumper wire from battery positive voltage to the left cooling fan low reference circuit of the left cooling fan electrical connector.

Does the right cooling fan operate in high speed?

Go to Step 19

Go to Step 23

12

Does the right cooling fan operate in high speed?

Go to Step 13

Go to Step 16

13

  1. Disconnect the cooling fan 2 relay
  2. Connect a 20-amp fused jumper between the left cooling fan low reference circuit of the cooling fan 2 relay and the ground circuit of the cooling fan 2 relay.

Does the left cooling fan operate properly in high speed?

Go to Step 15

Go to Step 20

14

Inspect for poor connections at the cooling fan 1 relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 29

Go to Step 24

15

Inspect for poor connections at the cooling fan 2 relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 29

Go to Step 25

16

Inspect for poor connections at the cooling fan 3 relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 29

Go to Step 26

17

Inspect for poor connections at the harness connector of the right cooling fan. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 29

Go to Step 27

18

Inspect for poor connections at the harness connector of the left cooling fan. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 29

Go to Step 28

19

Repair the left cooling fan motor supply voltage circuit. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 29

--

20

Repair the left cooling fan motor ground circuit. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 29

--

21

Repair the right cooling fan motor ground circuit. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 29

--

22

Repair the right cooling fan motor supply voltage circuit. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 29

--

23

Repair the left cooling fan low reference circuit. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 29

--

24

Replace the cooling fan 1 relay.

Did you complete the replacement?

Go to Step 29

--

25

Replace the cooling fan 2 relay.

Did you complete the replacement?

Go to Step 29

--

26

Replace the cooling fan 3 relay.

Did you complete the replacement?

Go to Step 29

--

27

Replace the right cooling fan. Refer to Engine Coolant Fan Motor Replacement .

Did you complete the replacement?

Go to Step 29

--

28

Replace the left cooling fan. Refer to Engine Coolant Fan Motor Replacement .

Did you complete the replacement?

Go to Step 29

--

29

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3