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Three Speed Fan Operation

Although the PCM output circuits are called low, medium and high fan control (FC), cooling fan operation is controlled by a combination of these outputs  .

REFER to  FAN CONTROL  for more information  .

Fig 1: Identifying Low Fan Control (LFC) Relay Connector
G03626752Courtesy of FORD MOTOR CO.
NOTE: The VPWR & LFC circuits may be reversed in the harness connector. Also, the LFC circuit may be wired to 2 separate relays. REFER to the appropriate SYSTEM WIRING DIAGRAMS article for additional information.
Fig 2: Identifying Medium Fan Control (MFC) Relay Connector
G03626753Courtesy of FORD MOTOR CO.
NOTE: The VPWR & MFC circuits may be reversed in the harness connector. Also, the MFC circuit may be wired to 2 separate relays. REFER to the appropriate SYSTEM WIRING DIAGRAMS article for additional information.
Fig 3: Identifying High Fan Control (HFC) Relay Connector
G03626754Courtesy of FORD MOTOR CO.
NOTE: The VPWR & HFC circuits may be reversed in the harness connector. Also, the HFC circuit may be wired to 2 separate relays. REFER to the appropriate SYSTEM WIRING DIAGRAMS article for additional information.