Diagnostic Aids

WARNING: This page does not describe the selected car, but rather 32 other vehicles, including the 2003 Mercury Sable, 2003 Mercury Mountaineer, 2003 Mercury Marauder, 2003 Mercury Grand Marquis, and 2003 Lincoln Town Car. However, it is still accessible from the selected car via links, so may be relevant.

This system test is for Aviator, Escape, Focus, Ranger 2.3L, Sable, Taurus and Windstar only. On all models, PCM determines engine cooling fan requirements and controls fan operation through Low Fan Control (LFC), Medium Fan Control (MFC), and High Fan Control (HFC) circuits.

While performing these tests, use the wiring diagrams included in TEST KF. Wiring diagrams in SYSTEM WIRING DIAGRAMS article may use different terminology.

Perform this test only when instructed by QUICK TEST or directed by other test procedures. This test is only intended to diagnose:

Wiring Harness Circuits (B+, FAN PWR & VPWR, IGN START/RUN, LFC, MFC & HFC). See Fig 1-Fig 10
Low Speed Fan Control (LFC), Medium Speed Fan Control (MFC) & High Speed Fan Control (HFC) Relays
Powertrain Control Module (PCM)

Fig 1: Identifying Cooling Fan Circuits (Aviator)

G00190996

Courtesy of FORD MOTOR CO.

Fig 2: Identifying Cooling Fan Circuits (Escape 2.0L)

G00005701

Courtesy of FORD MOTOR CO.

Fig 3: Identifying Cooling Fan Circuits (Escape 3.0L - Early)

G00190993

Courtesy of FORD MOTOR CO.

Fig 4: Identifying Cooling Fan Circuits (Escape 3.0L - Late)

G00190994

Courtesy of FORD MOTOR CO.

Fig 5: Identifying Cooling Fan Circuits (Focus 2.0L With A/C)

G00190991

Courtesy of FORD MOTOR CO.

Fig 6: Identifying Cooling Fan Circuits (Focus 2.3L With A/C)

G00190992

Courtesy of FORD MOTOR CO.

Fig 7: Identifying Cooling Fan Circuits (Focus Without A/C)

G00190995

Courtesy of FORD MOTOR CO.

Fig 8: Identifying Cooling Fan Circuits (Ranger 2.3L)

G00005703

Courtesy of FORD MOTOR CO.

Fig 9: Identifying Cooling Fan Circuits (Sable & Taurus)

G00088387

Courtesy of FORD MOTOR CO.

Fig 10: Identifying Cooling Fan Circuits (Windstar)

G00013301

Courtesy of FORD MOTOR CO.

COOLING FAN RELAY LOCATIONS

Application & Relay

Location

Aviator

Auxiliary Junction Box

Escape

2.0L

HFC, LFC, MFC

Battery Junction Box, In Engine Compartment

3.0L

HFC No. 1 (MAIN FAN) & No. 2 (ADD FAN 2) & LFC

Battery Junction Box, In Engine Compartment

MFC (ADD FAN 3)

Located On Driver's Side Of Fan Shroud

Focus

With A/C

HFC, LFC & MFC

Battery Junction Box, In Engine Compartment

Without A/C

⁽¹⁾

Battery Junction Box, In Engine Compartment

Ranger 2.3L

⁽¹⁾

Battery Junction Box, In Engine Compartment

Sable & Taurus

HFC No. 1 & No. 2

Battery Junction Box, In Engine Compartment

LFC (Fan Braking Relay) & MFC

Located In Relay Center Box No. 1 On Left Side Of Engine Compartment

Windstar

HFC & LFC

Battery Junction Box, In Engine Compartment

⁽¹⁾	Equipped with one cooling fan relay.