LEMON Manuals: Even more car manuals for everyone
Home >> Chevrolet >> 2000 >> Metro Base, 2D Hatchback >> Repair and Diagnosis >> Engine Mechanical >> Cooling Fan >> Engine Cooling Fan System - Troubleshooting >> Electric Cooling Fan Circuit Diagnosis >> 3.1L "W" Body (Lumina) >> Procedure No. 3

Procedure No. 3

  1. If cooling fan functional check has been performed, go to next step. If cooling fan functional check has not been performed, see COOLING FAN FUNCTIONAL CHECK .
  2. Using scan tool, command low speed fans on. Command high speed fans on while observing fans. If both fans operate with no change, go to step  8. If both fans did not operate with no change, go to next step.
  3. If engine coolant fan motor 1 stopped operating, go to step  9. If engine coolant fan motor 1 did not stop operating, go to next step.
  4. Disconnect fan control relay 3. Probe high speed fans control circuit (Dark Blue wire) at fan control relay 3 connector using test light connected to battery voltage. Using scan tool, command high speed fans on. If test light illuminates after a few seconds, go to next step. If test light does not illuminate after a few seconds, go to step  12.
  5. Probe coil feed circuit (Red wire) at fan control relay 3 connector using test light connected to ground. If test light illuminates, go to next step. If test light does not illuminate, go to step  13.
  6. Probe switch feed circuit (Red wire) at fan control relay 3 connector using test light connected to ground. If test light illuminates, go to next step. If test light does not illuminate, go to step  14.
  7. Install fused jumper (30-amp) between switch feed circuit (Red wire) and engine coolant fan motor 2 feed circuit (White wire) at fan control relay 3 connector. If engine coolant fan motor 2 turns on, go to step  15. If engine coolant fan motor 2 does not turn on, go to step  16.
  8. Turn ignition off. Disconnect PCM. Disconnect fan control relay 1. Install fused jumper (30-amp) between switch feed circuit (Red wire) and engine coolant fan motor 1 feed circuit (Light Blue wire) at fan control relay 1 connector. Turn ignition on, engine off. Probe high speed fans control circuit (Dark Blue wire) at PCM harness connector using fused jumper connected to ground. If fans switch from low to high speed, go to step  22. If fans do not change from low to high speed, go to step  17.
  9. Disconnect fan control relay 2. Probe high speed fans control circuit (Dark Blue wire) at fan control relay 2 connector using test light connected to battery voltage. Using scan tool, command high speed fans on. If test light illuminates after a few seconds, go to next step. If test light does not illuminate after a few seconds, go to step  18.
  10. Probe ground circuit (Black wire) at fan control relay 2 connector using test light connected to battery voltage. If test light illuminates, go to next step. If test light does not illuminate, go to step  19.
  11. Probe coil feed circuit (Orange wire) at fan control relay 2 connector using test light connected to ground. If test light illuminates, go to step  20. If test light does not illuminate, go to step  21.
  12. Repair open in high speed fans control circuit (Dark Blue wire) between fan control relay 3 and PCM. After repairs, perform COOLING FAN FUNCTIONAL CHECK .
    13. NOTE: If fuse is open, locate and repair short to ground on load circuit or shorted component.
  13. Repair open or short in fan control relay 3 coil feed circuit (Red wire). After repairs, perform COOLING FAN FUNCTIONAL CHECK .
    14. NOTE: If fuse is open, locate and repair short to ground on load circuit or shorted component.
  14. Repair open in fan control relay 3 switch feed circuit (Red wire). After repairs, perform COOLING FAN FUNCTIONAL CHECK .
  15. Replace fan control relay 3. After repairs, perform COOLING FAN FUNCTIONAL CHECK .
  16. Repair open in engine coolant fan motor 2 feed circuit (White wire) between fan control relay 3 and engine coolant fan motor 2. After repairs, perform COOLING FAN FUNCTIONAL CHECK .
  17. Repair open or short to battery voltage in high speed fans control circuit (Dark Blue wire). After repairs, perform COOLING FAN FUNCTIONAL CHECK .
  18. Repair open in high speed fans control circuit (Dark Blue wire) between fan control relay 2 and PCM. After repairs, perform COOLING FAN FUNCTIONAL CHECK .
  19. Repair open in ground circuit (Black wire). After repairs, perform COOLING FAN FUNCTIONAL CHECK .
  20. Replace fan control relay 2. After repairs, perform COOLING FAN FUNCTIONAL CHECK .
    21. NOTE: If fuse is open, locate and repair short to ground on load circuit or shorted component.
  21. Repair open in fan control relay 2 coil feed circuit (Orange wire). After repairs, perform COOLING FAN FUNCTIONAL CHECK .
  22. Check PCM connectors for poor connections. If problem was found, repair as necessary. After repairs, perform COOLING FAN FUNCTIONAL CHECK . If problem was not found, go to next step.
  23. Replace PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article in ENGINE PERFORMANCE. After repairs, perform COOLING FAN FUNCTIONAL CHECK .
scientia non olet · About LEMON Manuals