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Pinpoint Test KF: Fan Control Relays: Introduction

This pinpoint test is intended to diagnose the following:

Although the PCM output circuits are called LFC, MFC, and HFC, cooling fan operation is controlled by a combination of these outputs.

COOLING FAN STATE

  PCM Output Low Speed Medium Speed High Speed
Vehicles With 5 Fan Control Relays LFC ON ON ON
  MFC OFF ON ON
  HFC OFF OFF ON
All Others LFC ON N/A ON
  HFC OFF N/A ON
Fig 1: Charge Air Cooler Cooling Fan Relay Connector
G13533296Courtesy of FORD MOTOR CO.

Harness Side

Circuit Pin
VPWR (Vehicle Power) 1
B+ (Battery Positive Voltage) 3
CACCF (Charge Air Cooler Cooling Fan) 2
FANPWR (Fan Power) 5
Fig 2: Charge Air Cooler Cooling Fan Motor Connector
G13533297Courtesy of FORD MOTOR CO.

Harness Side

Circuit Pin
FANPWR (Fan Power) 1
GND (Ground) 2
Fig 3: Cooling Fan Motor 1 Connector
G13533298Courtesy of FORD MOTOR CO.

Harness Side

Circuit Pin
FANPWR (Fan Power) 1
FC (Fan Control) 2
Fig 4: Cooling Fan Motor 2 Connector
G13533299Courtesy of FORD MOTOR CO.

Harness Side

Circuit Pin
FANPWR (Fan Power) 1
GND (Ground) 2
Fig 5: Fan Control 1 (FC1) Relay Connector
G13533300Courtesy of FORD MOTOR CO.

Harness Side

Circuit Pin
VPWR (Vehicle Power) 2
B+ (Battery Positive Voltage) 3
LFC (Low Fan Control) 1
FANPWR (Fan Power) 5
Fig 6: Fan Control 2 (FC2) Relay Connector
G13533301Courtesy of FORD MOTOR CO.

Harness Side

Circuit Pin
VPWR (Vehicle Power) 2
HFC (High Fan Control) 1
FANPWR (Fan Power) 4
FGC (Fan Ground Control) 3
GND (Ground) 5
NOTE: The HFC circuit may be wired to the FC3 and FC5 relays. Refer to the Wiring Diagrams Manual for additional information.
Fig 7: Fan Control 3 (FC3) Relay Connector
G13533302Courtesy of FORD MOTOR CO.

Harness Side

Circuit Pin
VPWR (Vehicle Power) 2
B+ (Battery Positive Voltage) 5
HFC (High Fan Control) 1
FANPWR (Fan Power) 3
NOTE: The MFC circuit may be wired to the FC2 and FC4 relays. Refer to the Wiring Diagrams Manual for additional information.
Fig 8: Fan Control 4 (FC4) Relay Connector
G13533303Courtesy of FORD MOTOR CO.

Harness Side

Circuit Pin
VPWR (Vehicle Power) 1
MFC (Medium Fan Control) 2
FANRSTR2 (Fan Resistor 2) 4
FANPWR (Fan Power) 5
Fig 9: Fan Control 5 (FC5) Relay Connector
G13533304Courtesy of FORD MOTOR CO.

Harness Side

Circuit Pin
HFC (High Fan Control) 2
Fig 10: Powertrain Control Module (PCM) Connector - For PCM Connector Views
G13533305Courtesy of FORD MOTOR CO.

Harness Side

Circuit Pin
HFC (High Fan Control) B39
LFC (Low Fan Control) B43