Ford F150 Pickup. Instruction - part 1473

 
Place gear selector in Drive. Obey all local traffic laws and accelerate heavily to 35 MPH. Coast 
down to idle speed and stop vehicle. 

M/T Equipped Vehicles 
 
Accelerate and shift from first to second gear. Continue to accelerate moderately to 40 MPH. Coast 
down to idle speed and stop vehicle.  

After third drive cycle, perform QUICK TEST. If any Continuous Memory DTCs are present, go to 
appropriate system test. See DIAGNOSTIC TROUBLE CODE DEFINITIONS. If Continuous 
Memory DTCs are not present, testing is complete. 

TEST DG: KNOCK SENSOR 

Diagnostic Aids 

Perform this test only when directed by QUICK TEST. This test is intended to diagnose the following.  

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Knock Sensor (KS)  

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Wiring Harness Circuits; (KS & SIG RTN)  

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Powertrain Control Module (PCM)  

To prevent replacement of good components, be aware the following non-EEC related areas may be at fault:  

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Poor Fuel Quality  

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Ignition System  

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Ignition Or Valve Timing  

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Engine Mechanical Condition  

Testing 

1) For KOER & Continuous Memory Only DTCs P0325, P0326 (KS1), Or P0330 & P0331 (KS2): 
Check KS Sensor Resistance 
DTCs P0325, P0326, P0330 and P0331 indicate spark knock voltage exceeded maximum calibrated limit. 
DTC P0325 and P0326 are for knock sensor No. 1 (cylinder bank that includes cylinder No. 1). DTCs 
P0330 and P0331 are for knock sensor No. 2. Possible causes for these faults are. 

NOTE:

After each service or repair procedure has been completed, reconnect all 
components. Clear DTCs and perform DRIVE CYCLE. Ensure COMPREHENSIVE 
COMPONENT MONITOR is performed. After drive cycle is complete, repeat 
QUICK TEST procedures to ensure all EEC-V systems are working properly and 
DTCs are no longer present.

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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Open In KS Circuit  

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KS Circuit Shorted To PWR Or GND  

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Faulty Knock Sensor  

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Faulty Powertrain Control Module (PCM)  

Turn ignition switch to OFF position. Ensure knock sensor is connected. Perform DRIVE CYCLE. 
Ensure COMPREHENSIVE COMPONENT MONITOR is performed. Disconnect KS, measure 
resistance through the KS harness connector pins. If resistance is 4.39-5.35 megohms, go to next step. If 
resistance is less than 4.39 megohms, go to step 3). 

2) Check For Open KS Circuit Between KS Harness Connector & PCM Harness Connector 
 
Turn ignition switch to OFF position. Disconnect PCM. Using DVOM, measure resistance of the KS (+) 
and KS (-) circuits between the PCM harness connector pin and the KS harness connector. If each 
resistance is less than 5.0 ohms, replace KS. If either resistance is 5.0 ohms or more, repair open circuit. 
Perform DRIVE CYCLES. 

3) Check KS Circuit For Short To Ground In Harness 
 
Turn ignition switch to OFF position. Disconnect KS connector. Using a DVOM, measure resistance 
between the KS (+) and KS (-) circuits at the PCM harness connector and chassis GND. If each resistance 
is greater than 10,000 ohms, go to next step. If either resistance is less than 10,000 ohms, repair short 
circuit. Perform DRIVE CYCLES. 

4) Check KS Circuits For Short To Power In Harness 
 
Disconnect PCM. Turn ignition switch to ON position. Using DVOM, measure voltage between the KS 
(+) circuit at the PCM harness connector and battery negative post. If the voltage is less than 0.5 volt, 
replace PCM. Perform DRIVE CYCLES. For continuous DTCs, go to next step. If voltage is not less 
than 0.5 volt, repair short circuit. Perform DRIVE CYCLES. 

5) Check KS Circuit For Intermittent Fault 
 
Turn ignition switch to OFF position. Disconnect PCM connector(s). Measure the resistance for KS (+) 
and KS (-) circuits between the PCM and KS harness connectors, while viewing the ohmmeter, grasp the 
vehicle harness as close to the knock sensor(s) as possible. Shake and bend a small section of the harness 
from the KS sensor to the PCM. Tap the PCM and KS connectors if possible. If the resistance readings 
change, isolate fault and repair. Perform DRIVE CYCLES. If resistance does not change, go to next 
step. 

7) Check Internal PCM Resistance 
 
Disconnect PCM connector(s). Using a DVOM, measure resistance between PCM connector KS (+) and 
KS (-) terminals. If resistance is more than 10 k/ohms, replace knock sensor. If concern is still present, 
replace PCM. Perform DRIVE CYCLES. If resistance is 10 k/ohms or less, replace PCM. Perform 
DRIVE CYCLES.  

 

2003 Ford Pickup F150 

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

  

TEST DH: THROTTLE POSITION SENSOR

Diagnostic Aids 

Perform this test only when directed by QUICK TEST. This test is intended to diagnose the following:  

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TP Sensor  

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Binding Or Sticking Throttle Linkage  

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Wiring Harness Circuits (PWR GND, SIG RTN, TP, VPWR & VREF)  

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Powertrain Control Module (PCM)  

Normal range of throttle angle measurement for TP sensor is 0-96.6 degrees. To pass QUICK TEST procedure, 
range of throttle rotation (in degrees) must be within 3 percent of specification. To prevent replacement of good 
components, be aware the following non-EEC related areas may be at fault:  

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Idle Speed  

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Binding Throttle Shaft Or Linkage  

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TP Sensor Not Seated  

Testing 

1) For KOEO & KOER Only DTC P1124: Check For Other DTCs 
DTC P1124 is set when TP sensor rotation angle or voltage reading is less than 13.27 percent (.66 volt), 
or is more than 23.52 percent (1.17 volt) during KOEO or KOER self-test. Possible causes for this fault 
are: 

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Binding Or Bent Throttle Linkage  

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TP Sensor Not Seated Properly  

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Throttle Plate Below Closed Throttle Position  

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Throttle Plate Screw Misadjusted  

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Faulty TP Sensor  

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Faulty Powertrain Control Module (PCM)  

Perform KOEO ON-DEMAND SELF-TEST and KOER ON-DEMAND SELF-TEST . Check for 
DTC P0405 or P1400. If DTC P0405 or P1400 is present along with P1124, see DIAGNOSTIC 
TROUBLE CODE DEFINITIONS. If DTC P0405 or P1400 are not present with DTC P1124, go to 
next step. 

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:

For additional testing information, see DIAGNOSTIC AIDS.

 

2003 Ford Pickup F150 

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

  

2) Check For Binding Throttle Plate Or Linkage 
 
Inspect throttle linkage and plate for binding. Ensure throttle plate is at closed position. If throttle linkage 
and/or plate is binding, or if throttle plate is not at closed position, repair as necessary. If throttle moves 
freely, opens fully and returns to closed throttle position and no mechanical concern is found, go to step 
8). 

3) For KOEO, KOER & Continuous Memory DTC P1120: Check For Frayed Wires Or Corrosion 
On Connector Terminals 
DTC P1120 is set when TP sensor rotation angle or voltage reading remains within calibrated range but 
falls between 3.42-9.85 percent (.17-.49 volt) during KOEO or KOER self-test. Possible causes for this 
fault are: 

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Frayed Or Corroded Circuit Wires Or Connectors  

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VREF Circuit Open To TP  

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VREF Circuit Shorted To SIG RTN Circuit  

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Loose Connector Or Terminals At TP Sensor  

Inspect TP sensor connector for loose, damaged or corroded terminals. Inspect wiring harness between 
TP sensor and PCM for damage or corrosion. Repair as necessary. If no concern is found, go to next step. 

4) Check For Stuck TP Sensor 
 
Turn ignition switch to OFF position. Connect scan tool to Data Link Connector (DLC). Turn ignition 
switch to ON position. Using scan tool, access TP and TP V PID from PID/DATA MONITOR & 
RECORD menu. While observing TP V PID, slowly move throttle plate from closed to wide open throttle 
position. If TP reading or (TP V) PID value indicates any sudden drop to less than 9.85 percent (.49 volt), 
go to next step. If TP and TP V PID readings increase and decrease gradually and smoothly, go to step 
20). 

5) Check Voltage Between VREF & SIG RTN Circuits To TP Sensor 
 
Turn ignition switch to OFF position. Disconnect TP sensor connector. Turn ignition switch to ON 
position. Using a DVOM, measure voltage between VREF and SIG RTN terminals at TP sensor harness 
connector. See Fig. 163, Fig. 165 and Fig. 166 . If voltage is 4-6 volts, go to next step. If voltage is not 4-
6 volts, reconnect TP sensor and go to TEST C, step 1). 

6) Check TP Circuit For Open In Harness 
 
Turn ignition switch to OFF position. Disconnect PCM connector(s). Inspect connector for loose, 
damaged or corroded terminals and repair as necessary. Using a DVOM, measure resistance of TP circuit 
between PCM harness connector and TP sensor harness connector. See Fig. 163, Fig. 165 and Fig. 166 . 
If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in TP circuit. 

NOTE:

For additional testing information, see DIAGNOSTIC AIDS.

 

2003 Ford Pickup F150 

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