Preliminary Information

This article contains only the text required to test electric cooling fans. Other diagnostic information may be referenced while performing electric cooling fan diagnosis. See appropriate ENGINE PERFORMANCE articles for complete information on engine control systems.

To help save diagnostic time, always check for blown fuses or fusible links before proceeding with any testing. If fuses are blown, locate and repair short circuit before replacing fuses. See appropriate FUSES & CIRCUIT BREAKERS article in ELECTRICAL. Ensure all related relay and wire harness connections are clean and tight. Repair as necessary. See WIRING DIAGRAMS  for component, terminal and wire color identification.