Your Vehicle: 2001 Ford Escort ZX2 L4-2.0L DOHC VIN 3
 
Vehicle » Powertrain Management » Computers and Control Systems » Testing and Inspection » Pinpoint Tests » KF: Fan Control (FC) Relay - Pinpoint Test » KF1 - KF60  
 
 
  KF1 - KF60  
 

KF: Fan Control (FC) Relay

KF: Introduction See: KF: Fan Control (FC) Relay - Introduction

KF1 DTC P1474/P1477/P1479 or FC PRIMARY CIRCUIT FAULT: CHECK VPWR (or IGN START/RUN for ESCAPE) VOLTAGE TO APPLICABLE FAN CONTROL RELAY

  • NOTE: During diagnosis, use the chart below to determine the correct circuit and relay being tested.

  

  • Disconnect appropriate fan control relay.
  • Key on, engine off.
  • Measure VPWR (IGN START/RUN for Escape) circuit voltage at the applicable fan control relay harness connector.

Is voltage greater than 10.5 volts?
Yes

  • GO to KF2

.

No

  • REPAIR open VPWR (or IGN START/RUN) circuit to the applicable

fan control relay.

KF2 CHECK FOR LFC, MFC or HFC CIRCUIT CYCLING

  • Key on, engine off.
  • Connect a non-powered test lamp between the VPWR (or IGN START/RUN) circuit and the LFC, MFC or HFC circuit at the applicable fan control relay harness connector.
  • Access Output Test Mode on scan tool.
  • While observing test lamp, command the appropriate cooling fan speed on and off (for Escape, commanding the low speed fan on will also command the medium speed fan output on).

Does the test lamp turn on and off when the cooling fan output is commanded on and off?
Yes

  • REPLACE appropriate fan control relay.

No

  • REPEAT test step to VERIFY results. If test lamp still does

not turn on and off as expected, turn KEY OFF. REMOVE test lamp. GO to KF3
.

KF3 CHECK LFC, MFC or HFC CIRCUIT FOR SHORT TO POWER IN HARNESS

  • Disconnect PCM.
  • Key on, engine off.
  • Measure voltage between the LFC, MFC or HFC circuit at the applicable fan relay harness connector and ground.

Is voltage less than 1.0 volt?
Yes

  • KEY OFF. GO to KF4

.

No

  • REPAIR short circuit.

KF4 CHECK LFC, MFC or HFC CIRCUIT FOR SHORT TO GROUND IN HARNESS

  • Disconnect scan tool from DLC.
  • Measure resistance between the LFC, MFC or HFC circuit at the applicable fan relay harness connector and ground.

Is resistance greater than 10,000 ohms?
Yes

  • GO to KF5

.

No

  • REPAIR short circuit.

KF5 CHECK FOR OPEN LFC, MFC or HFC CIRCUIT

Note: Refer to the PCM connector pin numbers at the beginning of this pinpoint test.

  • Measure resistance of the LFC, MFC or HFC circuit between the appropriate PCM harness connector pin (LFC, MFC or HFC) and the appropriate fan control relay harness connector.

Is resistance less than 5.0 ohms?
Yes

No

  • REPAIR open circuit.

KF7 DTC P1479 (3.0L Escape) CHECK IGNITION START/RUN CIRCUIT VOLTAGE TO HIGH SPEED FC RELAY #1

  • Disconnect high speed FC relay #1 (MAIN FAN in BJB).
  • Key on, engine off.
  • Measure IGN START/RUN circuit voltage at the high speed FC relay #1 harness connector.

Is voltage greater than 10.5 volts?
Yes

  • GO to KF8

.

No

  • REPAIR open IGN START/RUN circuit.

KF8 CHECK FOR HFC CIRCUIT CYCLING AT HIGH SPEED FC RELAY #1

  • Connect a non-powered test lamp between the IGN START/RUN circuit and the HFC circuit at the high speed FC relay #1 harness connector.
  • Access Output Test Mode on scan tool.
  • While observing test lamp, command the high speed cooling fan on and off.

Does the test lamp turn on and off when the high speed cooling fan output is commanded on and off?
Yes

  • REPLACE high speed FC relay #1.

No

  • Leave test lamp connected. GO to KF9

.

KF9 CHECK FOR HFC CIRCUIT CYCLING WITH HIGH SPEED FC RELAY #2 DISCONNECTED

  • The non-powered test lamp still connected between the IGN START/RUN circuit and the HFC circuit at the high speed FC relay #1 harness connector.
  • Cooling fans commanded off.
  • Disconnect high speed FC relay #2 (ADD FAN 2 in BJB).
  • While observing test lamp, again command the high speed cooling fan on and off.

Does the test lamp now turn on and off when the high speed cooling fan output is commanded on and off?
Yes

  • REPLACE high speed FC relay #2.

No

  • GO to KF3

to diagnose the HFC circuit. Make checks
at the high speed FC relay #1 harness connector.

KF10 CONTINUOUS MEMORY DTC P1474: CHECK LOW SPEED FAN CONTROL (LFC) CIRCUIT FOR OPEN OR SHORT TO POWER

  • A/C and defrost off.
  • Disconnect cooling fan connector (both for applications with two fans).
  • Connect a non-powered test lamp between the (LOW) FAN PWR circuit and ground circuit at the cooling fan harness connector. For applications with two fans, connect light to the following fan harness connector:
  • Driver's side for 2.0L Escape.
  • Passenger side for 3.0L Escape.
  • Other applications with two fans, either one can be used.
  • Key on, engine off.
  • Access Output Test Mode on scan tool.
  • Command Low Speed Fan on.
  • Observe test lamp for an indication of a fault while completing the following (the lamp will turn off when a fault is detected, indicating an open or short to power):
  • Shake, wiggle and bend the LFC circuit between the PCM and (low speed) FC relay.
  • Shake, wiggle and bend the VPWR (or IGN START/RUN) circuit to the (low speed) FC relay.
  • Lightly tap on the (low speed) FC relay to simulate road shock.

Is a fault indicated?
Yes

  • ISOLATE fault and REPAIR as necessary.

No

  • GO to KF11

.

KF11 CHECK LFC CIRCUIT FOR SHORT TO GROUND

  • Key on, engine off.
  • Command Low Speed Fan off.
  • Observe test lamp for an indication of a fault while completing the following (the lamp will turn on when a fault is detected, indicating LFC circuit short to ground):
  • Shake, wiggle and bend the LFC circuit between the PCM and (low speed) FC relay.
  • Lightly tap on the (low speed) FC relay to simulate road shock.

Is a fault indicated?
Yes

  • ISOLATE fault and REPAIR as necessary.

No

.

KF15 CONTINUOUS MEMORY DTC P1477: CHECK MEDIUM SPEED FAN CONTROL (MFC) CIRCUIT FOR OPEN OR SHORT TO POWER

  • A/C and defrost off.
  • Disconnect both cooling fans.
  • For 2.0L Escape:
  • Connect a non-powered test lamp between the MEDIUM FAN PWR circuit and ground circuit at the passenger side cooling fan harness connector.
  • For 3.0L Escape:
  • Disconnect medium speed FC relay (ADD FAN 3, on fan shroud).
  • Connect a non-powered test lamp between the MFC circuit and IGN START/RUN circuit at the medium speed FC relay harness connector.
  • Key on, engine off.
  • Access Output Test Mode on scan tool.
  • Command Low Speed Fan on (this also commands on the medium speed fan).
  • Observe test lamp for an indication of a fault while completing the following (the lamp will turn off when a fault is detected, indicating an open or short to power):
  • Shake, wiggle and bend the LFC circuit between the PCM and medium speed FC relay.
  • Shake, wiggle and bend the IGN START/RUN circuit to the medium speed FC relay.
  • For 2.0L, lightly tap on the medium speed FC relay to simulate road shock.

Is a fault indicated?
Yes

  • ISOLATE fault and REPAIR as necessary.

No

  • GO to KF16

.

KF16 CHECK MFC CIRCUIT FOR SHORT TO GROUND

  • Key on, engine off.
  • Command Low Speed Fan off.
  • Observe test lamp for an indication of a fault while completing the following (the lamp will turn on when a fault is detected, indicating MFC circuit short to ground):
  • Shake, wiggle and bend the MFC circuit between the PCM and medium speed FC relay.
  • For 2.0L, lightly tap on the medium speed FC relay to simulate road shock.
  • For 3.0L, inspect medium speed FC relay for intermittent concerns.

Is a fault indicated?
Yes

  • ISOLATE fault and REPAIR as necessary.

No

.

KF20 CONTINUOUS MEMORY DTC P1479: CHECK HIGH SPEED FAN CONTROL (HFC) CIRCUIT FOR OPEN OR SHORT TO POWER

  • A/C and defrost off.
  • Disconnect cooling fan connector(s) (both for applications with two fans).
  • Connect a non-powered test lamp between the (HIGH) FAN PWR circuit and ground circuit at the cooling fan harness connector (for applications with two fans; passenger side for 2.0L Escape, driver's side for 3.0L Escape, either one for others).
  • Key on, engine off.
  • Access Output Test Mode on scan tool.
  • Command High Speed Fan on.
  • Observe test lamp for an indication of a fault while completing the following (the lamp will turn off when a fault is detected, indicating an open or short to power):
  • Shake, wiggle and bend the HFC circuit between the PCM and high speed FC relay.
  • Shake, wiggle and bend the VPWR (IGN START/RUN for Escape) circuit to the high speed FC relay (for 3.0L Escape, both relays).
  • Lightly tap on the high speed FC relay to simulate road shock.

Is a fault indicated?
Yes

  • ISOLATE fault and REPAIR as necessary.

No

  • GO to KF21

.

KF21 CHECK HFC CIRCUIT FOR SHORT TO GROUND

  • Command High Speed Fan off.
  • Observe test lamp for an indication of a fault while completing the following (the lamp will turn on when a fault is detected, indicating an HFC circuit short to ground):
  • Shake, wiggle and bend the HFC circuit between the PCM and high speed FC relay.
  • Lightly tap on the HFC relay to simulate road shock.

Is a fault indicated?
Yes

  • ISOLATE fault and REPAIR as necessary.

No

.

KF25 ONE OR ALL FAN SPEEDS INOPERATIVE: CHECK FAN CONTROL FAULT PIDs TO VERIFY FAN CONTROL PRIMARY CIRCUITS

  • Verify A/C is off, and engine temperature is below the temperature where the cooling fan would come on.
  • Key on, engine off.
  • Access the LFCF, MFCF and HFCF PIDs (as appropriate, according to which circuits the vehicle has)(for Escape, early builds will not have the MFCF PID).

Does the LFCF, MFCF or HFCF PID indicate YES?
Yes

  • For the fault PID(s) that are YES, a primary circuit fault is

indicated for that circuit.

  • For 3.0L Escape with HFCF PID indicating YES:
  • GO to KF7

.

  • All others:
  • GO to KF1

.

No

  • For Escape:

.

  • GO to KF85

.

  • All others:
  • GO to KF30

.

KF30 ELECTRIC COOLING FAN CONCERN (WITH NO DTCs): CHECK FAN FUNCTION

  • Key on, engine off.
  • Access Output Test Mode on scan tool.
  • Command the cooling fan on and check for fan operation. For two speed fan applications, check both fan speeds (wait 20 seconds after commanding high speed fan on, verify fan speed changes).

Does the fan(s) operate (all speeds)?
Yes

  • KEY OFF. Cooling fan circuits OK. RETURN to

Section 3 See: Symptom Related Diagnostic Procedures.

No

  • COMMAND cooling fan off. REMAIN in Output Test Mode.
  • For Focus (with A/C), Cougar and Windstar

:

  • GO to KF50

.

  • For Focus (without A/C) and Ranger:
  • Fan will not operate. GO to KF41

.

  • All others

:

  • GO to KF31

.

KF31 DID THE FAN(S) OPERATE AT ANY SPEED?

Note: For applications with two cooling fan motors, if one cooling fan motor does not operate when the other motor operates, GO to KF70.
During the operational check of both fan speeds, did the fan(s) operate at any speed?
Yes

  • Only one fan speed is operational. GO to KF40

.

No

  • Cooling fan will not operate at any speed. GO to KF32

.

KF32 COOLING FAN WILL NOT OPERATE AT ANY SPEED: COMMAND HIGH SPEED FAN ON AND CHECK FOR VOLTAGE TO COOLING FAN

  • Key on, engine off.
  • Still in Output Test Mode, with fan commanded off.
  • Disconnect cooling fan(s) (both for applications with two fans).
  • Command high speed fan on.
  • Measure voltage between the HIGH FAN PWR circuit at the cooling fan harness connector (either one for Taurus/Sable) and chassis ground.

Is voltage greater than 10.0 volts?
Yes

  • KEY OFF. Power is being supplied to fan.
  • For Taurus/Sable:
  • GO to KF130

(to check fan braking relay and ground circuits).

  • All others:
  • GO to KF37

(to check cooling fan ground circuit).

No

  • KEY OFF. Power is not being supplied to fan. GO to KF33

.

KF33 CHECK B+ TO HIGH SPEED FC RELAY AND LOW SPEED FC RELAY

  • Disconnect high speed and low speed FC relays.
  • Measure B+ circuit voltage at the high speed FC relay harness connector.
  • Measure B+ circuit voltage at the low speed FC relay harness connector.

Is voltage greater than 10.0 volts?
Yes

  • GO to KF34

.

No

  • B+ circuit fault. CHECK condition of related fuses. If OK, REPAIR

open circuit. If fuse is damaged, CHECK B+ and FAN PWR circuits for short
to ground before replacing.

KF34 CHECK FOR OPEN HIGH FAN PWR AND LOW FAN PWR CIRCUITS

  • Measure resistance of the HIGH FAN PWR circuit between the High Speed FC relay harness connector and the cooling fan harness connector(s). Resistance should be less than 5.0 ohms.
  • Measure resistance of the LOW FAN PWR circuit between the low speed FC relay harness connector and the cooling fan harness connector(s). Resistance should be less than 5.0 ohms (7.0 ohms for Taurus/Sable).

Do the HIGH FAN PWR and LOW FAN PWR circuits check OK?
Yes

  • GO to KF35

.

No

  • REPAIR open circuit (for Taurus/Sable, if open is in LOW FAN

PWR circuit, verify condition of resistor that is in circuit).

KF35 COMMAND LOW SPEED FAN ON AND CHECK FOR VOLTAGE TO COOLING FAN

  • Reconnect low speed FC relay and high speed FC relay.
  • Key on, engine off.
  • Again, enter Output Test Mode on scan tool.
  • Command Low Speed Fan on.
  • Measure LOW FAN PWR circuit voltage at the cooling fan harness connector (either one for applications with two fans).

Is voltage greater than 10.0 volts?
Yes

  • KEY OFF. REPLACE the High Speed FC relay, then GO to KF37

(for
Taurus/Sable, GO to KF130
).

No

  • KEY OFF. GO to KF75

, and follow directions for low
speed fan inoperative. After repair, GO to KF75
and follow directions
for high speed fan inoperative.

KF37 CHECK COOLING FAN GROUND CIRCUIT

  • Disconnect scan tool from DLC.
  • Measure resistance of ground circuit between the cooling fan harness connector and chassis ground.

Is resistance less than 5.0 ohms?
Yes

  • REPLACE fan motor(s).

No

  • REPAIR ground circuit.

KF40 DETERMINE WHICH FAN SPEED IS OPERATIONAL

Is the low speed fan operational?
Yes

  • High speed fan inoperative. GO to KF46

.

No

  • Low speed fan inoperative. GO to KF41.

KF41 (LOW SPEED) FAN INOPERATIVE: COMMAND LOW SPEED FAN ON AND CHECK FOR VOLTAGE TO COOLING FAN

Note: The following steps apply to applications with either a one or two speed fan. Refer to the fan speed in parenthesis as appropriate.

  • Key on, engine off.
  • Still in Output Test Mode with fan commanded off.
  • Disconnect cooling fan(s) (both for applications with two fans).
  • Command low speed fan on.
  • Measure (LOW) FAN PWR circuit voltage at the cooling fan harness connector (either one for applications with two fans).

Is voltage greater than 10.0 volts?
Yes

  • For Taurus/Sable:
  • REPLACE fan.
  • All others:
  • VERIFY ground circuit to fan. If OK, REPLACE fan motor.

No

  • KEY OFF. GO to KF42

.

KF42 CHECK B+ VOLTAGE TO (LOW SPEED) FAN CONTROL (FC) RELAY

  • Disconnect (Low Speed) FC relay.
  • Measure B+ circuit voltage at the (low speed) FC relay harness connector.

Is voltage greater than 10.5 volts?
Yes

  • GO to KF43

.

No

  • VERIFY condition of related fuse. If OK, REPAIR open B+ circuit.

If fuse was damaged CHECK B+ and (LOW) FAN PWR circuit for short to ground
before replacing.

KF43 CHECK FOR OPEN (LOW) FAN PWR CIRCUIT

  • Measure resistance of the (LOW) FAN PWR circuit between the (low speed) FC relay harness connector and the cooling fan harness connector(s).

Is resistance less than 5.0 ohms (7.0 ohms for Taurus/Sable)?
Yes

  • GO to KF75

.

No

  • REPAIR open circuit (for Taurus/Sable, verify condition of resistor

that is in circuit).

KF46 HIGH SPEED FAN INOPERATIVE: COMMAND HIGH SPEED FAN ON AND CHECK FOR VOLTAGE TO COOLING FAN

  • Key on, engine off.
  • Still in Output Test Mode with fan commanded off.
  • Disconnect cooling fan(s) (both for applications with two fans).
  • Command high speed fan on.
  • Measure HIGH FAN PWR circuit voltage at the cooling fan harness connector.

Is voltage greater than 10.0 volts?
Yes

  • For Taurus/Sable:
  • REPLACE fan.
  • All others:
  • VERIFY ground circuit to fan. If OK, REPLACE fan motor.

No

  • KEY OFF. GO to KF47

.

KF47 CHECK B+ VOLTAGE TO HIGH SPEED FAN CONTROL (FC) RELAY

  • Disconnect high speed FC relay.
  • Measure B+ circuit voltage at the high speed FC relay harness connector.

Is voltage greater than 10.5 volts?
Yes

  • GO to KF48

.

No

  • VERIFY condition of related fuse. If OK, REPAIR open B+ circuit.

If fuse was damaged, CHECK B+ and HIGH FAN PWR circuit for short to ground
before replacing.

KF48 CHECK FOR OPEN HIGH FAN PWR CIRCUIT

  • Measure resistance of the HIGH FAN PWR circuit between the high speed FC relay harness connector and the cooling fan harness connector.

Is resistance less than 5.0 ohms?
Yes

  • GO to KF75

.

No

  • REPAIR open circuit.

KF50 LOW AND/OR HIGH SPEED COOLING FAN DOES NOT OPERATE: CHECK FOR B+ TO HIGH SPEED FC AND LOW SPEED FC RELAYS

Note: For applications with two cooling fan motors, if one motor does not operate when the other motor operates, GO to KF70.

  • Disconnect high speed FC and low speed FC relays.
  • Measure B+ circuit voltage at both high speed FC and low speed FC relay harness connectors.

Are both voltages greater than 10.5 volts?
Yes

  • GO to KF51

.

No

  • VERIFY condition of related fuses. If OK, REPAIR open B+ circuit.

If fuse was damaged, CHECK B+ and fan(s) PWR circuits for short to ground
before replacing.

KF51 CHECK FOR OPEN FAN PWR, FAN GROUND AND INTERNAL FAN CIRCUITS

  • Measure resistance between battery negative post and the FAN PWR circuit at both the high speed FC and low speed FC relay harness connectors.

Are both resistances less than 15.0 ohms?
Yes

  • GO to KF52

.

No

  • GO to KF56

.

KF52 CHECK FAN PWR CIRCUIT FOR SHORT TO GROUND IN HARNESS

  • Disconnect both cooling fans.
  • Measure resistance between the FAN PWR circuit in harness and ground.

Is resistance greater than 10,000 ohms?
Yes

  • GO to KF53

.

No

  • REPAIR FAN PWR circuit short to ground.

KF53 CHECK HIGH SPEED FC AND LOW SPEED FC RELAY OPERATION

  • Reconnect high speed FC and low speed FC relays.
  • Key on, engine off.
  • Access Output Test Mode on scan tool.
  • Check high speed FC relay operation:
  • Command high speed fan on, wait 15 seconds.
  • Measure voltage to the FAN PWR circuit at the cooling fan harness connector (either one).
  • Voltage must be greater than 10.5 volts.
  • Check low speed FC relay operation:
  • Command low speed fan on.
  • Measure voltage to the FAN PWR circuit at the cooling fan connector (either one).
  • Voltage must be greater than 10.0 volts.

Do the high speed FC and low speed FC relays operate correctly?
Yes

  • REPLACE cooling fan(s).

No

  • KEY OFF. NOTE which fan speed was inoperative. GO to KF75

.

KF56 CHECK FOR OPEN FAN PWR CIRCUIT BETWEEN COOLING FAN AND THE HIGH SPEED FC AND LOW SPEED FC RELAYS

  • Disconnect cooling fan (either one).
  • Measure resistance of FAN PWR circuit between cooling fan harness connector and both the high speed FC and low speed FC relay harness connectors.

Are both resistances less than 15.0 ohms?
Yes

  • GO to KF57

.

No

  • REPAIR open in FAN PWR circuit (if open is only between low

speed FC relay and fan, first verify dropping resistor connection).

KF57 CHECK COOLING FAN GROUND CIRCUIT

  • Measure resistance of ground circuit between the cooling fan harness connector and chassis ground.

Is resistance less than 5.0 ohms?
Yes

  • REPLACE inoperative cooling fan(s).

No

  • REPAIR ground circuit.

KF60 LOW, MEDIUM AND/OR HIGH SPEED COOLING FAN ALWAYS RUNS (NO DTCS): VERIFY FAN IS NOT ON BECAUSE OF A/C HIGH PRESSURE SWITCH INPUT TO PCM

  • Start engine.
  • Access ACP PID.

Is the ACP PID "CLOSED"?
Yes

  • The PCM will turn the cooling fan on when the A/C high pressure

switch input is "closed". Leave engine running. GO to KF61
.

No

  • Input OK. GO to KF65.

Continued: See: KF61 - KF136