Ford F150 Pickup. Instruction - part 1459

step 9). If secondary ignition on all other vehicles is okay, go to next step. 

WARNING:

Always refer to safety procedures to reduce possibility of injury. See 
FUEL SYSTEM SAFETY PRECAUTIONS.

 

2003 Ford Pickup F150 

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

  

Fig. 167: Fuel System Types, Fuel Injector Resistances & Pressure Specifications 
Courtesy of FORD MOTOR CO. 

7) Check Fuel Pressure 

 

2003 Ford Pickup F150 

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

  

Turn ignition switch to OFF position. Release fuel pressure. See FUEL SYSTEM PRESSURE RELEASE 
under FUEL SYSTEMS in appropriate REMOVAL & INSTALLATION article. Install fuel pressure 
gauge. With scan tool connected, turn ignition switch to ON position. Using scan tool, access OUTPUT 
TEST MODE. See OUTPUT TEST MODE under ADDITIONAL SYSTEM FUNCTIONS. Command 
fuel pump ON. If fuel pressure is as specified, go to next step. See Fig. 167. If fuel pressure is not as 
specified, turn ignition switch to OFF position and go to TEST HC, step 1). 

8) Check Fuel Pressure Leakdown 
 
Leave fuel pressure gauge installed and ignition switch turned to ON position. Using scan tool, access 
OUTPUT TEST MODE. See OUTPUT TEST MODE under ADDITIONAL SYSTEM FUNCTIONS. 
Command fuel pump ON to obtain maximum fuel pressure. Exit OUTPUT TEST MODE and turn 
ignition switch to OFF position. If fuel pressure remains within 5 psi (34 kPa) of maximum pressure for 
one minute after turning ignition switch to OFF position, go to next step. If fuel pressure does not remain 
within 5 psi (34 kPa), go to TEST HC, step 1). 

9) Check VPWR Circuit At Fuel Injectors 
Disconnect at least 2 fuel injector connectors, one from each bank. Turn ignition switch to ON position. 
Using a DVOM, measure voltage of VPWR circuit at disconnected fuel injector connectors. If any 
voltage measurement is 10.5 volts or less, repair VPWR circuit. If voltage measurements are more than 
10.5 volts, go to step 15) (natural gas vehicles), or go to next step (all other vehicles). 

10) Check Fuel Injectors Ability To Deliver Fuel 
Turn ignition switch to OFF position. Release fuel pressure. See appropriate FUEL SYSTEM 
PRESSURE RELEASE procedure under FUEL SYSTEM VENTING in REMOVAL & 
INSTALLATION article. Install fuel pressure gauge. Cycle ignition switch to ON and then to OFF 
positions several times. Locate and disconnect Inertia Fuel Shutoff (IFS) switch connector. See 
INERTIA FUEL SHUTOFF SWITCH LOCATIONS table. Monitor fuel pressure gauge while 
cranking engine for at least 5 seconds. If fuel pressure drops more than 5 psi (34 kPa) while cranking 
engine, EEC system is not cause of no-start. Return to NO-START/NORMAL CRANK symptom under 
SYMPTOMS in TROUBLE SHOOTING - NO CODES - CNG, FLEX-FUEL & GASOLINE article. If 
fuel pressure does not drop more than 5 psi (kPa), replace PCM. 

INERTIA FUEL SHUTOFF SWITCH LOCATIONS 

NOTE:

A no-start condition can occur only if more than 50 percent of fuel 
injectors are without power.

WARNING:

Always refer to safety procedures to reduce possibility of injury. See 
FUEL SYSTEM SAFETY PRECAUTIONS.

NOTE:

A break in step numbering sequence occurs at this point. Procedure skips 
from step 10) to step 15). No test procedures have been omitted.

Application

Location

Aviator, Blackwood, Econoline, Escape, Excursion, Expedition, 

Behind Right Kick Panel

 

2003 Ford Pickup F150 

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

  

15) Check Fuel Pressure (Natural Gas Vehicles) 
Turn ignition switch to OFF position. With scan tool connected to DLC, access FRP PID (fuel pressure). 
Turn ignition switch to ON position. Record fuel pressure and compare results with specifications. See 
Fig. 167. If fuel pressure is within specification on scan tool and pressure gauge, go to next step. If fuel 
pressure is not within specification on scan tool and pressure gauge, go to TEST HB, step 1). 

16) Check Injector Signal From Natural Gas Vehicle Module 
 
Turn ignition switch to OFF position. Connect a 12-volt test light between injector signal circuit and 
VPWR circuit terminal at fuel injector harness connector. Crank engine while observing test light. If test 
light glows dimly while cranking engine, replace PCM and go to step 6). If test light does not glow as 
specified, go to TEST HA, step 47). 

17) Check PCM Driver To Coils 
 
Turn ignition switch to OFF position. Connect 12-volt test light between B+ and each coil driver circuit at 
harness connector. Crank engine while observing test light. Repeat procedure for each coil driver. Test 
light should blink brightly, once for each engine revolution. If test light blinks as specified, go to step 6). 
If test light does not blink as specified, go to TEST JD, step 1).  

TEST B: EEC-V POWER RELAY 

Diagnostic Aids 

Explorer, Mountaineer, Navigator, Pickup & Ranger
Crown Victoria, Grand Marquis Marauder & Town Car

Left Front Side Of Luggage

Compartment, Behind Lining

Focus

Bottom Of Right "A" Pillar

LS

Behind Left Kick Panel

Mustang

In Left Rear Of Luggage

Compartment

RV Cutaway

On Lower Right Of Steering Column

Sable & Taurus

In Right Side Of Luggage

Compartment. Behind Side Panel

Thunderbird

In Left Side Front Footwell

Windstar

On Right Rear Side Of Vehicle

ZX2

Bottom Of Left "A" Pillar

WARNING:

Always refer to safety procedures to reduce possibility of injury. See 
FUEL SYSTEM SAFETY PRECAUTIONS.

NOTE:

After each service or repair procedure has been completed, reconnect all 
components. Clear DTCs and repeat QUICK TEST procedures to ensure all EEC-
V systems are working properly and DTCs are no longer present.

 

2003 Ford Pickup F150 

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