z
Spark (EEC-Controlled)
To prevent replacement of good components, be aware the following non-EEC related areas and components
may be cause of concern:
z
Fuel Quality & Quantity
z
Ignition (General Condition)
z
Engine Mechanical Components
z
Starter & Battery Circuits
Testing
1) Check Passive Anti-Theft System (Securi-Lock)
If vehicle does not have an anti-theft system, go to next step. If vehicle has an anti-theft system, it may be
activated causing the no-start condition. Verify by observing anti-theft indicator light being illuminated
on instrument panel, or a DTC P1260 may be present. If anti-theft system is not activated, go to next step.
If anti-theft system is activated, see appropriate ANTI-THEFT SYSTEMS article in ACCESSORIES &
EQUIPMENT for diagnosis and testing.
2) Attempt To Crank Engine
Ensure Inertia Fuel Shutoff (IFS) switch is closed (button pushed in). Attempt to start engine. If engine
does not crank, check vehicle starting and charging systems. See appropriate STARTERS or
GENERATORS & REGULATORS article in STARTING & CHARGING SYSTEMS. Repair as
necessary and retest. If engine cranks, go to next step.
3) Check For Intermittent No Start
Attempt to start engine. If engine now starts, fault is intermittent. Go to TEST Z, step 2). If engine does
not start, go to next step.
4) Check VREF Voltage To TP Sensor
Turn ignition switch to OFF position. Disconnect TP sensor. Turn ignition switch to ON position. Using a
DVOM, measure voltage between circuits VREF and SIG RTN at TP sensor harness connector. See Fig.
163-Fig. 166 . If voltage is 4-6 volts, turn ignition switch to OFF position, reconnect TP sensor connector
and go to next step. If voltage is not 4-6 volts, turn ignition switch to OFF position and go to TEST C,
step 1).
2003 Ford Pickup F150
2003 ENGINE PERFORMANCE Self-Diagnostics - CNG, Flex-Fuel & Gasoline