LEMON Manuals: Even more car manuals for everyone
Home >> Saturn >> 2000 >> SW2 Automatic >> Repair and Diagnosis >> Engine Mechanical >> Cooling Fan >> Engine Cooling Fan System - Troubleshooting >> Electric Cooling Fan Circuit Diagnosis >> 3.0L CATERA >> Auxiliary Cooling Fan Runs Continuously

Auxiliary Cooling Fan Runs Continuously

  1. Perform COOLING FAN SYSTEM CHECK . Go to next step.
  2. Turn ignition off. Ensure engine temperature is less than 203°F (95°C). Install A/C manifold gauge set to check A/C compressor refrigerant pressure switch is less than 217psi. If auxiliary engine coolant fan 1, auxiliary engine coolant fan 2 , and electric cooling fan all operating at low speed, go to next step. If auxiliary engine coolant fan 1, auxiliary engine coolant fan 2 , and electric cooling fan all operating at low speed, go to step  6.
  3. Check diagnostic enable circuit (Brown/Blue wire) of fan control relay K26 for short to ground. If problem was found, repair as necessary. After repairs, go to step  29. If problem was not found, go to next step.
    4. CAUTION: Installation of proper relay is critical. If an enhanced relay (equipped with a diode) is installed into a position requiring a standard relay (equipped without a diode) excessive current will damage any components associated with relay or its associated circuits.
  4. Check control circuit (terminal No. 6) of relay coil of fan control relay K26 for short to ground. If problem was found, repair as necessary. After repairs, go to step  29. If problem was not found, go to next step.
  5. Replace primary cooling fan temperature switch. After repairs, go to step  29.
  6. If electric cooling fan is operating at low speed, go to step  10. If electric cooling fan is not operating at low speed, go to next step.
  7. If auxiliary engine coolant fan 1 and auxiliary engine coolant fan 2 are operating at low speed, go to next step. If auxiliary engine coolant fan 1 and auxiliary engine coolant fan 2 are not operating at low speed, go to step  15.
  8. Remove fan control relay K26. Connect test light between supply voltage circuit (terminal No. 2) of auxiliary engine coolant fan 1 of fan control relay K26 connector and ground. If test light illuminates, go to next step. If test light does not illuminate, go to step  11.
  9. Remove fan control relay K87. Connect test light between supply voltage circuit (terminal No. 3) of relay coil of fan control relay K87 connector and ground. If test light illuminates, see DIAGNOSTIC SYSTEM CHECK in appropriate AUTOMATIC A/C-HEATER SYSTEMS article. . If test light does not illuminate, go to step  12.
  10. Check supply voltage circuit (terminal No. 4) of electric cooling fan of fan control relay K26 connector for short to voltage. If problem was found, repair as necessary. After repairs, go to step  29. If problem was not found, go to step  13.
  11. Replace fan control relay K26. After repairs, go to step  29.
  12. Check supply voltage circuit of auxiliary engine coolant fan 1 of fan control relay K26 connector (terminal No. 2) and fan control relay K87 connector (terminal No. 8) for short to voltage. If problem was found, repair as necessary. After repairs, go to step  29. If problem was not found, go to step  14.
  13. Replace fan control relay K26. After repairs, go to step  29.
  14. Replace fan control relay K87. After repairs, go to step  29.
  15. Turn ignition on, engine off. If auxiliary engine coolant fan 2 operates at high speed, go to next step. If auxiliary engine coolant fan 2 does not operate at high speed, go to step  24.
  16. Remove fan control relay K28. Using DVOM, check continuity between control circuit (terminal No. 6) of relay coil of fan control relay K28 connector and ground. If continuity exists, go to next step. If continuity does not exist, go to step  19.
  17. Check control circuit (terminal No. 6) of relay coil of fan control relay K28 for short to ground. If problem was found, repair as necessary. After repairs, go to step  29. If problem was not found, go to next step.
  18. Replace secondary cooling fan temperature switch. After repairs, go to step  29.
  19. Using DVOM, check continuity between control circuit (terminal No. 5) of relay coil of fan control relay K28 from A/C compressor refrigerant pressure switch and ground. If continuity exists, go to next step. If continuity does not exist, go to step  22.
  20. Check control circuit (terminal No. 5) of relay coil of fan control relay K28 from A/C compressor refrigerant pressure switch for short to ground. If problem was found, repair as necessary. After repairs, go to step  29. If problem was not found, go to next step.
  21. Replace A/C compressor refrigerant pressure switch. After repairs, go to step  29.
  22. Check supply voltage circuit (Red/White wire) of auxiliary engine coolant fan 2 for short to voltage. If problem was found, repair as necessary. After repairs, go to step  29. If problem was not found, go to next step.
  23. Replace fan control relay K28. After repairs, go to step  29.
  24. If electric cooling fan operates at high speed, go to next step. If electric cooling fan does not operate at high speed, go to step  29.
  25. Remove fan control relay K67. Check control circuit (terminal No. 6) of relay coil of fan control relay K67 connector for short to ground. If problem was found, repair as necessary. After repairs, go to step  29. If problem was not found, go to next step.
  26. Replace primary cooling fan temperature switch. After repairs, go to step  29.
  27. Check supply voltage circuit (terminal No. 4) of electric cooling fan of fan control relay K67 connector for short to voltage. If problem was found, repair as necessary. After repairs, go to step  29. If problem was not found, go to next step.
  28. Replace fan control relay K67. After repairs, go to next step.
  29. Connect all connectors and components that were disconnected. Verify auxiliary engine coolant fans 1 and 2 operate properly.
scientia non olet · About LEMON Manuals