Ford F150 Pickup. Instruction - part 1562

 
Disconnect A/C high pressure switch. See A/C HIGH PRESSURE SWITCH LOCATIONS table. 
Using scan tool, access ACP PID from PID/DATA MONITOR & RECORD menu. If ACP PID indicates 
CLOSED, go to next step to check A/C high pressure switch input to PCM. If ACP PID indicates OPEN, 
turn ignition switch to OFF position and reconnect A/C high pressure switch. Check for over-pressurized 
A/C system. Service A/C system as necessary. See appropriate article in AIR CONDITIONING & 
HEATING. If A/C system is not over-pressurized, replace A/C high pressure switch. 

A/C HIGH PRESSURE SWITCH LOCATIONS 

62) Check ACPSW Circuit For Short To Ground In Harness 
 
Turn ignition switch to OFF position. Disconnect scan tool from DLC. Disconnect PCM connector. Using 
a DVOM, measure resistance between PCM harness connector terminal No. 86 and chassis ground. See 
PCM CONNECTOR IDENTIFICATION. If resistance is more than 10 k/ohms, replace PCM. If 
resistance is 10 k/ohms or less, repair short to ground in ACPSW circuit. 

63) Low &/Or High Speed Cooling Fan Always Runs (No DTCs): Ensure Fan Is Not On Because Of 
A/C High Pressure Sensor Input To PCM 
Turn ignition switch to OFF position. Turn A/C off. Connect scan tool to Data Link Connector (DLC). 
Start engine and allow to idle. Using scan tool, access ACP V PID from PID/DATA MONITOR & 
RECORD menu. See PARAMETER IDENTIFICATION MODE under ADDITIONAL SYSTEM 
FUNCTIONS. If ACP V PID voltage reading is 3 volts or less, input is not causing cooling fan to 
operate. Go to step 65). If ACP V PID voltage reading is more than 3 volts, turn ignition switch to OFF 
position. Check A/C system for high system pressure. Service A/C system as necessary. See appropriate 
article in AIR CONDITIONING & HEATING. 

Application

Location

Crown Victoria, Grand Marquis 
& Town Car

On High Pressure Line Right Side Of Engine, Near Top Of Valve

Cover

Escape

On High Pressure Line In Right Front Corner Of Engine

Compartment, Behind Headlight

Focus

On High Pressure Line In Lower Right Front Corner Of Engine

Compartment, Behind Headlight

Ranger 2.3L

In Left Front Corner Of Engine Compartment, Near High Pressure

Tap

Sable & Taurus

On A/C Manifold At Rear Of Compressor

NOTE:

Perform test step 63) when directed from ELECTRIC COOLING FAN 
ALWAYS ON symptom under SYMPTOMS in TROUBLE SHOOTING - NO 
CODES - CNG, FLEX-FUEL & GASOLINE article.

NOTE:

A break in step numbering sequence occurs at this point. Procedure skips 
from step 63) to step 65). No test procedures have been omitted.

NOTE:

Ensure A/C and defroster are off.

 

2003 Ford Pickup F150 

2003 ENGINE PERFORMANCE Self-Diagnostics - CNG, Flex-Fuel & Gasoline

  

65) Check For LFC Relay Always Closed 
Turn ignition switch to OFF position. Remove LFC relay. See COOLING FAN RELAY LOCATIONS
table. Turn ignition switch to ON position. Check cooling fan operation. If cooling fan does not continue 
to operate, go to step 80). If cooling fan continues to operate, repair short to PWR in FAN PWR circuit 
(Focus without A/C and Ranger), or go to next step (all others). 

66) Check HFC Relay 
Leave LFC relay removed. Turn ignition switch to OFF position. Remove HFC relay. See COOLING 
FAN RELAY LOCATIONS table. Turn ignition switch to ON position. Check cooling fan operation. If 
cooling fan does not continue to operate, go to step 80). If cooling fan continues to operate, perform the 
following: 

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Focus, Ranger & Windstar 
 
Turn ignition switch to OFF position. Repair short to PWR in FAN PWR circuit. Recheck cooling 
fan operation. 

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Escape 2.0L 
 
Turn ignition switch to OFF position and go to step 68). 

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Escape 3.0L 
 
If passenger's side cooling fan continues to operate, repair short to PWR in LOW FAN PWR 
circuit. If driver's side cooling fan continues to operate, repair short to PWR in HIGH FAN PWR 
circuit. 

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All Others 
 
Go to next step.  

67) Check LOW FAN PWR Circuit For Short To PWR In Harness 
 
Turn ignition switch to OFF position. Disconnect cooling fan connector(s). Turn ignition switch to ON 
position. Using a DVOM, measure voltage between negative battery terminal and LOW FAN PWR 
circuit at cooling fan harness connector. See Fig. 329. If voltage is less than one volt, repair short to PWR 
in HIGH FAN PWR circuit. Recheck cooling fan operation. If voltage is one volt or more, repair short to 
PWR in LOW FAN PWR circuit. Recheck cooling fan operation. 

68) Check MFC Relay 
 
Ensure LFC and HFC relays are removed. Turn ignition switch to OFF position. Remove MFC relay 
from battery junction box located in engine compartment. Turn ignition switch to ON position. Check 

NOTE:

In the following steps, HFC relay on Escape 3.0L is referred to as HFC No. 
1 (MAIN FAN).

 

2003 Ford Pickup F150 

2003 ENGINE PERFORMANCE Self-Diagnostics - CNG, Flex-Fuel & Gasoline

  

cooling fan operation. If cooling fan does not continue to operate, turn ignition switch to OFF position 
and replace MFC relay. Recheck cooling fan operation. If both cooling fans continue to operate, turn 
ignition switch to OFF position and repair short to PWR in HIGH FAN PWR circuit. See Fig. 322. If 
only one cooling fan continues to operate, turn ignition switch to OFF position and repair short to PWR in 
either LOW FAN PWR or MEDIUM FAN PWR circuit at appropriate fan. 

70) One Cooling Fan Inoperative & Other Cooling Fan Operates Normally (No DTCs): Check For 
Open In Ground Circuit To Inoperative Cooling Fan 
 
Turn ignition switch to OFF position. Disconnect inoperative cooling fan connector. Using a DVOM, 
measure resistance of ground circuit between chassis ground and cooling fan harness connector. If 
resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in ground 
circuit. Recheck cooling fan operation. 

71) Command Cooling Fan ON & Check For PWR To Cooling Fan 
 
Disconnect remaining cooling fan (both cooling fans now disconnected). Using scan tool, access 
OUTPUT TEST MODE. See OUTPUT TEST MODE under ADDITIONAL SYSTEM FUNCTIONS. 
Command high speed fan ON. Using a DVOM, measure voltage between negative battery terminal and 
HIGH FAN PWR circuit at inoperative cooling fan harness connector. See Fig. 322-Fig. 326, Fig. 329 or 
Fig. 330 . If voltage is more than 10 volts, replace inoperative cooling fan and recheck cooling fan 
operation. If voltage is 10 volts or less, locate and repair open in FAN PWR circuit between inoperative 
cooling fan and splice to other cooling fan. Recheck fan operation. 

75) Attempt To Access PIDs With Scan Tool While In Output Test Mode 
Turn ignition switch to OFF position. Check if scan tool being used is capable of accessing PID values 
while in OUTPUT TEST MODE. See OUTPUT TEST MODE under ADDITIONAL SYSTEM 
FUNCTIONS. If scan tool is capable of accessing PIDs, go to next step to check primary circuits. If scan 
tool is not capable of accessing PIDs, proceed as follows: 

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If low speed fan is inoperative or cooling fan is inoperative for single-speed cooling fans, go to step 
77).  

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On Escape, if medium speed fan is inoperative, go to step 78).  

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On all models, if high speed fan is inoperative, go to step 79).  

76) Check Operation Of Low, Medium &/Or High Speed Cooling Fan Primary Circuits 

NOTE:

A break in step numbering sequence occurs at this point. Procedure skips 
from step 68) to step 70). No test procedures have been omitted.

NOTE:

A break in step numbering sequence occurs at this point. Procedure skips 
from step 71) to step 75). No test procedures have been omitted.

NOTE:

An inoperative low, medium or high speed cooling fan can be caused by a 
primary circuit fault, even though a DTC was not set. Step 76) will check 
primary circuit operation.

 

2003 Ford Pickup F150 

2003 ENGINE PERFORMANCE Self-Diagnostics - CNG, Flex-Fuel & Gasoline

  

 
Reconnect all cooling fans and reinstall all relays. Turn ignition switch to ON position. Using scan tool in 
OUTPUT TEST MODE, perform appropriate test procedure: 

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Low Speed Fan Inoperative (Cooling Fan Inoperative For Single Speed Cooling Fans) 
 
Using scan tool, access LFC and LFCF PIDs. With LFC PID OFF (low speed fan commanded OFF 
by PCM), LFCF PID should read NO (no fault). Command low speed fan ON. LFC PID should 
now read ON and LFCF PID should still read NO. 

z

Medium Speed Fan Inoperative (Escape) 
 
Using scan tool, access MFC and MFCF PIDs. If MFC and MFCF PIDs are not available, go to 
step 78). With MFC PID OFF (medium speed fan commanded OFF by PCM), MFCF PID should 
read NO (no fault). Command low speed fan ON (this commands medium fan ON). MFC PID 
should now read ON and MFCF PID should still read NO. 

z

High Speed Fan Inoperative 
 
Using scan tool, access HFC and HFCF PIDs. With HFC PID OFF (high speed fan commanded 
OFF by PCM), HFCF PID should read NO. Command high speed fan ON. HFC PID should read 
ON and HFCF PID should still read NO.  

If LFCF, MFCF and HFCF PIDs indicated YES with fan commanded ON or OFF, an LFC, MFC or HFC 
primary circuit fault is detected. If PID value was YES, go to step 1) and perform diagnosis for DTC 
P0480 (for LFCF PID), DTC P1477 (for MFCF PID), or DTC P0481 (for HFCF PID). If LFCF, MFCF or 
HFCF PIDs indicated NO with fan commanded ON and OFF, LFC, MFC or HFC primary circuits are 
okay. Replace appropriate LFC relay (if low speed fan is inoperative), MFC relay (if medium fan is 
inoperative) or HFC relay (if high speed fan is inoperative). Ensure applicable FAN PWR circuit is not 
shorted to ground. Recheck cooling fan operation. 

77) Check Operation Of Low Speed Cooling Fan Primary Circuits 
 
Reconnect cooling fan connector(s), as necessary. Turn ignition switch to ON position. Connect a test 
light between VPWR and LFC circuits at LFC relay cavities. See Fig. 322-Fig. 326, Fig. 329 or Fig. 
330 . Using scan tool, access OUTPUT TEST MODE. Observe test light while commanding low speed 
fan ON then OFF. If test light illuminates and then turns off, LFC primary circuits are okay. Replace LFC 
relay. Ensure FAN PWR circuit is not shorted to ground. Recheck cooling fan operation. If test light does 
not illuminate and then turn off, an LFC primary circuit fault is detected. Turn ignition switch to OFF 
position, go to step 1) and perform diagnosis for DTC P0480. 

78) Check Operation Of Medium Speed Cooling Fan Primary Circuits 
 
Reconnect cooling fan connector(s), as necessary. Turn ignition switch to ON position. Connect a test 
light between VPWR and MFC circuits at MFC relay cavities. See Fig. 322-Fig. 326, Fig. 329 or Fig. 
330 . Using scan tool, access OUTPUT TEST MODE. Observe test light while commanding low speed 
fan ON then OFF (this commands medium fan ON and OFF). If test light illuminates and then turns off, 

 

2003 Ford Pickup F150 

2003 ENGINE PERFORMANCE Self-Diagnostics - CNG, Flex-Fuel & Gasoline