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.

Trouble shoot cooling fan using appropriate diagnostic information provided. For cooling fan relay location, see COOLING FAN RELAY LOCATION table.

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. 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.

NOTE: Vehicles may be equipped with a PCM/ECM using an Electronically Erasable Programmable Read Only Memory (EEPROM). When replacing PCM/ECM, the new PCM/ECM must be programmed.