Test A: No-Start: 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 1-Fig 4 . 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).Courtesy of FORD MOTOR CO.
Courtesy of FORD MOTOR CO.
Courtesy of FORD MOTOR CO.
- 5) Check Flash EPROM (FEPS) Circuit For Short To Power
Using a DVOM, measure voltage between negative battery terminal and DLC terminal No. 13. See Fig 5 . If voltage is more than 9 volts, repair FEPS circuit for a short to VPWR. If voltage is 9 volts or less on models with coil-on-plug, go to step 17). If voltage is 9 volts or less on all others, go to next step. - 6) Check RPM PID In PCM
Turn ignition switch to OFF position. Using scan tool, access RPM PID from PID/DATA MONITOR & RECORD menu. Observe RPM PID on scan tool while cranking engine. If RPM PID does not indicate cranking speed, turn ignition switch to OFF position and go to TEST JD, step 1) . If RPM PID value indicates cranking speed, check secondary ignition components (ignition coils, spark plugs and wires). See TEST JB, step 1) . Repair as necessary. If secondary ignition on natural gas vehicles is okay, go to step 9). If secondary ignition on all other vehicles is okay, go to next step. - 7) Check Fuel Pressure
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 6. 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 LOCATIONSApplication Location Aviator, Blackwood, Econoline, Escape, Excursion, Expedition, Explorer, Mountaineer, Navigator, Pickup & Ranger Behind Right Kick Panel 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 - 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 FUEL PRESSURE SPECIFICATIONS . 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) .
NOTE:
Ensure scan tool is connected to a reliable power source with ignition switch in START position, such as vehicle battery. Ensure vehicle battery is fully charged.
WARNING:
Always refer to safety procedures to reduce possibility of injury. See FUEL SYSTEM SAFETY PRECAUTIONS
.
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.
WARNING:
Always refer to safety procedures to reduce possibility of injury. See FUEL SYSTEM SAFETY PRECAUTIONS
.