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Home >> Chevrolet >> 2002 >> Malibu Base >> Repair and Diagnosis >> Engine Mechanical >> Electric Cooling Fans >> System Testing >> Cooling Fan Inoperative

Cooling Fan Inoperative

  1. Did you perform the DIAGNOSTIC SYSTEM CHECK - ENGINE COOLING? If yes, go to next step. If no, go to DIAGNOSTIC SYSTEM CHECK - ENGINE COOLING  under SELF-DIAGNOSTIC.
  2. Install a scan tool. Turn ignition on, with engine off. With a scan tool, command the FANS LOW SPEED ON and OFF. Do the low speed engine cooling fans turn ON and OFF with each command? If yes, go to next step. If no, go to step  4 .
    NOTE: Before the PCM changes the speed of the cooling fans, a 3-second delay will occur.
  3. With a scan tool, command the FANS HIGH SPEED ON and OFF. Do the high speed engine cooling fans turn ON and OFF with each command? If yes, see INTERMITTENTS  in SYMPTOMS - ENGINE COOLING under TROUBLE SHOOTING. If no, go to step  11 .
  4. Test the fused battery positive voltage circuit of the cooling fan 1 relay for an open or short to ground. Did you find and correct the condition? If yes, go to step  30 . If no, go to next step.
  5. Test the cooling fan motor supply voltage circuit for a short to ground. Did you find and correct the condition? If yes, go to step  30 . If no, go to next step.
  6. Disconnect the cooling fan 1 relay. Connect the first 20-A 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? If yes, go to step  15 . If no, go to next step.
  7. Disconnect the cooling fan S/P relay. Connect the second 20-A fused jumper between the left cooling fan low reference circuit of the cooling fan S/P relay and the right cooling fan supply voltage circuit of the cooling fan S/P relay. Do both cooling fans operate in low speed? If yes, go to step  16 . If no, go to next step.
  8. Connect the second 20-A fused jumper between the battery positive voltage circuit of the cooling fan S/P relay and the cooling fan motor supply voltage circuit of the cooling fan S/P relay. Does the right cooling fan operate in high speed? If yes, go to step  11 . If no, go to next step.
  9. Install the cooling fan S/P relay. Disconnect the right cooling fan electrical connector. Connect 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? If yes, go to step  18 . If no, go to next step.
  10. Connect 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? If yes, go to step  22 . If no, go to step  23 .
  11. Install the cooling fan S/P relay. Disconnect the left cooling fan electrical connector. Connect the second 20-Amp fused jumper wire from the 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? If yes, go to step  19 . If no, go to next step.
  12. Connect the second 20-Amp fused jumper wire from battery positive voltage to the left cooling fan low reference circuit of the of the left cooling fan electrical connector. Does the right cooling fan operate in high speed? If yes, go to step  20 . If no, go to step  24 .
  13. Is the right cooling fan operating properly in high speed? If yes, go to next step. If no, go to step  17 .
  14. Disconnect the cooling fan S/P relay. Connect the second 20-A fused jumper between the left cooling fan low reference circuit of the cooling fan S/P relay and the ground circuit of the cooling fan S/P relay. Does the left cooling fan operate properly in high speed? If yes, go to step  16 . If no, go to step  21 .
  15. Inspect for poor connections at the cooling fan 1 relay. Did you find and correct the condition? If yes, go to step  30 . If no, go to step  25 .
  16. Inspect for poor connections at the cooling fan S/P relay. Did you find and correct the condition? If yes, go to step  30 . If no, go to step  26 .
  17. Inspect for poor connections at the cooling fan 2 relay. If yes, go to step  30 . If no, go to step  27 .
  18. Inspect for poor connections at the harness connector of the right cooling fan. If yes, go to step  30 . If no, go to step  28 .
  19. Inspect for poor connections at the harness connector of the left cooling fan. If yes, go to step  30 . If no, go to step  29 .
  20. Repair the left cooling fan supply voltage circuit. After repairs are complete, go to step  30 .
  21. Repair the left cooling fan ground circuit. After repairs are complete, go to step  30 .
  22. Repair the right cooling fan ground circuit. After repairs are complete, go to step  30 .
    NOTE: DO NOT remove the 20-A fused jumper wire connected during this step. Use a second 20-A fused jumper while performing the following steps.
  23. Repair the right cooling fan supply voltage circuit. After repair is complete, go to step  30 .
  24. Repair the left cooling fan low reference circuit. After repair is complete, go to step  30 .
  25. Replace the cooling fan 1 relay. After replacement is complete, go to step  30 .
  26. Replace the cooling fan S/P relay. After replacement is complete, go to step  30 .
  27. Replace the cooling fan 2 relay. After replacement is complete, go to step  30 .
  28. Replace the right cooling fan. See COOLING FAN  under REMOVAL & INSTALLATION. After replacement is complete, go to step  30 .
  29. Replace the left cooling fan. See COOLING FAN  under REMOVAL & INSTALLATION. After replacement is complete, go to next step.
  30. Operate the system in order to verify the repair. Did you correct the condition? If yes, then system is okay. If no, go to step  3 .
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