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Ford F150 Pickup. Instruction - part 1551

LS & Thunderbird

Connect a jumper wire between FPDM harness connector REM/FP PWR circuit and FP PWR
circuit terminals. Turn ignition switch to ON position. Using a DVOM, measure voltage between
negative battery terminal and fuel pump harness connector FP PWR terminal. If voltage is more
than 10.5 volts and is within .5 volt of voltage measured in step 72), turn ignition switch to OFF
position and remove jumper. Ensure all previous test step results are correct. Check all connectors
for corrosion or damage. If all previous results are correct and connectors are okay, replace REM.
If voltage is not as specified, isolate high resistance in FP PWR circuit and repair as necessary.

75) Check B+ To PCM Power Relay, CCRM, Fuel Pump Relay Or FPDM Power Supply Relay

Turn ignition switch to OFF position and proceed as follows:

Focus, Sable & Taurus

Remove FPDM power supply relay. Relay is located in battery junction box in left rear corner of
engine compartment. Turn ignition switch to ON position. Using a DVOM, measure voltage
between negative battery terminal and B+ circuit at FPDM power supply relay cavity No. 3. See
Fig. 307. If voltage is more than 10.5 volts, go to next step. If voltage is 10.5 volts or less,
insufficient voltage is being supplied to FPDM power supply relay. Check all related wiring and
connectors on B+ circuit to FPDM power supply relay for corrosion or damage. Repair as
necessary.

Mustang & ZX2

Disconnect Constant Control Relay Module (CCRM). On Mustang, CCRM is mounted on a
bracket behind engine coolant reservoir. On ZX2, CCRM is located in left front of engine
compartment. On all models, turn ignition switch to ON position. Using a DVOM, measure voltage
between negative battery terminal and B+ circuit at CCRM harness connector. See Fig. 310, Fig.
311 and Fig. 313 . If voltage is more than 10.5 volts, go to next step. If voltage is 10.5 volts or less,
insufficient voltage is being supplied to CCRM. Check all related wiring and connectors to CCRM
for corrosion or damage. Repair as necessary.

LS & Thunderbird

Remove fuel pump relay. Relay is located in battery junction box on right side of luggage
compartment. Turn ignition switch to ON position. Using a DVOM, measure voltage between
negative battery terminal and B+ circuit at fuel pump relay cavity No. 3. See Fig. 312. If voltage is
more than 10.5 volts, go to next step. If voltage is 10.5 volts or less, insufficient voltage is being
supplied to fuel pump relay. Check all related wiring and connectors on B+ circuit to fuel pump
relay for corrosion or damage. Repair as necessary.

76) Check FPDM PWR Circuit

NOTE:

A break in step numbering sequence occurs at this point. Procedure skips
from step 73) to step 75). No test procedures have been omitted.

2003 Ford Pickup F150

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

Turn ignition switch to OFF position and proceed as follows:

Focus, Sable & Taurus

Connect a jumper wire between FPDM power supply relay cavities No. 3 (B+) and No. 5 (FPDM
PWR). See Fig. 307. Using a DVOM, measure voltage between negative battery terminal and
FPDM PWR circuit at FPDM harness connector. See Fig. 309. If voltage is more than 10.5 volts,
ensure all previous test step results are correct. Check all connectors for corrosion or damage. If all
previous results are correct and connectors are okay, replace FPDM. If voltage is 10.5 volts or less,
isolate high resistance in system circuits and repair as necessary.

Mustang & ZX2

Connect a jumper wire between CCRM harness connector terminals No. 11 (B+) and No. 5 (FPDM
PWR). See Fig. 310 and Fig. 311 . Turn ignition switch to ON position. Using a DVOM, measure
voltage between negative battery terminal and FPDM PWR circuit at FPDM harness connector. If
voltage is more than 10.5 volts, ensure all previous test step results are correct. Check all
connectors for corrosion or damage. If all previous results are correct and connectors are okay,
replace FPDM. If voltage is 10.5 volts or less, isolate high resistance in system circuits and repair
as necessary.

LS & Thunderbird

Connect a jumper wire between fuel pump relay cavities No. 3 (B+) and No. 5 (REM/FP PWR).
See Fig. 312. Using a DVOM, measure voltage between negative battery terminal and REM/FP
PWR circuit at REM harness connector terminal No. 1. If voltage is more than 10.5 volts, ensure all
previous test step results are correct. Check all connectors for corrosion or damage. If all previous
results are correct and connectors are okay, replace REM. If voltage is 10.5 volts or less, isolate
high resistance in system circuits and repair as necessary.

80) Check FP RTN Circuit For Short To Ground

Turn ignition switch to OFF position. Disconnect REM 20-pin connector C420d (LS) or C420e
(Thunderbird). See Fig. 312. Turn ignition switch to ON position. Using a DVOM, measure voltage
between REM harness connector C420d (LS) or C420e (Thunderbird) terminals No. 1 (REM/FP PWR)
and No. 12 (FP RTN). If voltage is less than one volt, go to step 67). If voltage is one volt or more, repair
short to ground in FP RTN circuit.

NOTE:

A break in step numbering sequence occurs at this point. Procedure skips
from step 76) to step 80). No test procedures have been omitted.

NOTE:

A break in step numbering sequence occurs at this point. Procedure skips
from step 80) to step 85). No test procedures have been omitted.

NOTE:

Diagnostic procedures beginning with step 85) are performed when

2003 Ford Pickup F150

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

85) Perform REM Self-Test To Verify IFS Switch Input To REM
Using scan tool, perform Rear Electronics Module (REM) Self-Test. If DTC B2172 is present, go to next
step. If DTC B2172 is not present, go to TEST A, step 1).

86) DTC B2172: Check IFS Switch Input Circuit To REM

Turn ignition switch to OFF position. Disconnect REM 12-pin connector C420a. See Fig. 312. Turn
ignition switch to ON position. Using a DVOM, measure voltage between chassis ground and IFS INPUT
circuit at REM harness connector C420a (LS) or C420b (Thunderbird) terminal No. 8. If voltage is 10.5
volts or less, turn ignition switch to OFF position and ensure IFS switch is not open. If IFS switch is
okay, repair open circuit between IFS switch and REM harness connector. If voltage is more than 10.5
volts, perform the following:

If engine is a no-start and REM DTC B2172 was received in REM self-test mode, replace REM.

If engine will start or REM DTC B2172 is a Continuous Memory DTC, DTC is intermittent. If
engine is a no-start, return to NO START/NORMAL CRANK symptom under SYMPTOMS in
TROUBLE SHOOTING - NO CODES - CNG, FLEX-FUEL & GASOLINE article to continue
diagnosis. If engine will start, go to TEST Z, step 1). Although TEST Z is designed for PCM
intermittents, TEST Z will help in REM intermittent diagnosis.

TEST KC: FUEL SHUTOFF VALVE RELAY

Diagnostic Aids

Perform this test when instructed during QUICK TEST or if directed by other test procedures. This test is used
to diagnose the following:

Fuel Shutoff Valve (FSV) Relay

Inertia Fuel Shutoff (IFS) Switch

Wiring Harness Circuits (B+, FSV, FSVM, FSV PWR, GND & VPWR). See Fig. 315.

Powertrain Control Module (PCM)

directed here from NO START/NORMAL CRANK symptom under
SYMPTOMS in TROUBLE SHOOTING - NO CODES - CNG, FLEX-FUEL &
GASOLINE article.

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.

NOTE:

Fuel Shutoff Valve (FSV) relay may also be referred to as fuel valve relay (Crown
Victoria) or fuel pump relay (all others).

NOTE:

Any reference to Econoline applies to RV Cutaway unless otherwise indicated.

2003 Ford Pickup F150

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

Fig. 315: Identifying Fuel Shutoff System Circuits (Crown Victoria, Econoline & Pickup)
Courtesy of FORD MOTOR CO.

Testing

1) For KOEO & KOER Only DTC P0230: Check VPWR Voltage To FSV Relay
DTC P0230 is set when FSV output is commanded ON (grounded) and excessive current draw is detected
on FSV circuit; or when FSV output is commanded OFF, voltage is not detected on FSV circuit (PCM
expects VPWR voltage on FSV circuit to FSV relay coil). Possible causes are:

Open Or Shorted Fuel Shutoff Valve (FSV) Circuit

Open VPWR Circuit To FSV Relay

NOTE:

For additional testing information, see DIAGNOSTIC AIDS.

2003 Ford Pickup F150

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

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