Ford F150 Pickup. Instruction - part 1488

Fig. 215: Identifying TP Sensor Circuits & Connector Terminals 
Courtesy of FORD MOTOR CO. 

Testing 

10) For KOEO, KOER & Continuous Memory DTC P1115: Simulate Opposite Signal To PCM 
DTC P1115 indicates IAT2 sensor signal is more than self-test maximum of 4.6 volts. Possible causes for 
this fault are: 

z

Open Circuit In Harness  

z

IAT2 Signal Circuit Shorted To Power  

z

Faulty Connection  

z

Faulty IAT2 Sensor  

z

Faulty Powertrain Control Module (PCM)  

Turn ignition switch to OFF position. Connect scan tool to Data Link Connector (DLC). Disconnect IAT2 

NOTE:

Test procedure begins with step 10). No test procedures have been omitted.

NOTE:

For additional testing information, see DIAGNOSTIC AIDS.

NOTE:

If a scan tool communication concern exists, remove jumper wire and go 
to step 12).

 

2003 Ford Pickup F150 

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

  

sensor connector. Connect a jumper wire between IAT2 and SIG RTN circuits at IAT2 sensor harness 
connector. See Fig. 196 or Fig. 214 . Turn ignition switch to ON position. 

Using scan tool, access IAT2 PID from PID/DATA MONITOR & RECORD menu. If IAT2 PID voltage 
is less than .2 volt, replace IAT2 sensor. If IAT2 PID voltage is .2 volt or more, remove jumper wire and 
go to next step. 

11) Check IAT2 & SIG RTN Circuits For Open In Harness 
 
Turn ignition switch to OFF position. Disconnect PCM connector. Using a DVOM, measure resistance of 
IAT2 and SIG RTN circuits between PCM harness connector and IAT2 sensor harness connector. See 
Fig. 196 or Fig. 214 . Using a DVOM, measure resistance of IAT2 sensor and SIG RTN circuit between 
PCM harness connector terminal and IAT2 sensor harness connector terminal. If both resistance 
measurements are less than 5 ohms, replace PCM. If either resistance measurement is 5 ohms or more, 
repair open in affected circuit. 

12) Check IAT2 Circuit For Short To VREF In Harness 
 
Turn ignition switch to OFF position. Disconnect PCM connector. Using a DVOM, measure resistance 
between VREF circuits at PCM harness connector and IAT2 circuit at IAT2 sensor harness connector. 
See PCM CONNECTOR IDENTIFICATION and Fig. 196 or Fig. 214 . See PCM PWR GND, SIG 
RTN & VREF TERMINAL IDENTIFICATION table. If resistance is more than 10 k/ohms, replace 
PCM. If resistance is 10 k/ohms or less, repair short to VREF in IAT2 circuit. 

20) For KOEO, KOER & Continuous Memory DTC P1114: Simulate Opposite Signal To PCM 
DTC P1114 indicates IAT2 sensor signal is less than self-test minimum of .2 volt. Possible causes for this 
fault are: 

z

Grounded Circuit In Harness  

z

Faulty Connection  

z

Faulty IAT2 Sensor  

z

Faulty Powertrain Control Module (PCM)  

Disconnect IAT2 sensor connector. Connect scan tool to Data Link Connector (DLC). Turn ignition 
switch to ON position. Using scan tool, access IAT2 PID from PID/DATA MONITOR & RECORD 
menu. Turn ignition switch to OFF position. If IAT2 PID voltage is more than 4.2 volts, replace IAT2 
sensor. If IAT2 PID voltage is 4.2 volts or less, go to next step. 

21) Check VREF Voltage To TP Sensor 
 
Ensure ignition switch is in OFF position. Disconnect TP sensor connector. Turn ignition switch to ON 

NOTE:

A break in step numbering sequence occurs at this point. Procedure skips 
from step 12) to step 20). No test procedures have been omitted.

NOTE:

For additional testing information, see DIAGNOSTIC AIDS.

 

2003 Ford Pickup F150 

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

  

position. Using a DVOM, measure voltage between VREF and SIG RTN circuits at TP sensor harness 
connector. See Fig. 215. If voltage is 4-6 volts, VREF voltage is sufficient, reconnect TP sensor 
connector and go to next step. If voltage is not 4-6 volts, go to TEST C, step 1). 

22) Check IAT2 Circuit For Short To Ground In Harness 
 
Turn ignition switch to OFF position. Disconnect PCM connector. Using a DVOM, measure resistance 
between IAT2 circuit, SIG RTN, and PWR GND circuits at PCM harness connector. See PCM 
CONNECTOR IDENTIFICATION and Fig. 196 or Fig. 214 . See PCM PWR GND, SIG RTN & 
VREF TERMINAL IDENTIFICATION table. If both resistance measurements are more than 10 
k/ohms, replace PCM. If either resistance measurement is 10 k/ohms or less, repair short to ground in 
affected circuit. 

30) For KOEO, KOER & Continuous Memory DTC P0127: IAT2 Too High, Check Supercharger 
Intercooler Pump Operation 
DTC P0127 indicates that IAT2 sensor has detected a potential abnormality in intercooler system. This 
condition will cause boost from supercharger to by-pass to avoid potential engine damage. Possible 
causes for this fault are: 

z

Blocked Heat Exchangers  

z

Low Intercooler Fluid Level  

z

Intercooler Fluid Leakage  

z

Intercooler Pump Or Relay Failure  

z

Crossed Intercooler Coolant Lines  

Turn ignition switch to OFF position. Connect scan tool to Data Link Connector (DLC). Turn ignition 
switch to ON position. Using scan tool, access OUTPUT TEST MODE. Select ALL OUTPUTS ON. 
Command pump to run. If supercharger intercooler pump runs, go to next step. If supercharger intercooler 
pump does not run, go to TEST KP, step 8). 

31) Check Supercharger Intercooler System 
 
Make the following visual inspections: 

z

Intercooler Fluid Level  

z

Check For Cracked Coolant Lines  

z

Check For Blocked Heat Exchanger Or Coolant Lines  

z

Check For Crossed Coolant Lines  

Repair as necessary. If intercooler system is okay, go to next step.

NOTE:

A break in step numbering sequence occurs at this point. Procedure skips 
from step 22) to step 30). No test procedures have been omitted.

NOTE:

For additional testing information, see DIAGNOSTIC AIDS.

 

2003 Ford Pickup F150 

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

  

32) Simulate High IAT2 Voltage Signal 
 
Ensure scan tool is connected to DLC. Turn ignition switch to ON position. Using scan tool, access IAT2 
PID from PID/DATA MONITOR & RECORD menu. Monitor IAT2 PID voltage while disconnecting 
IAT2 sensor connector. If IAT2 PID voltage is more than 4 volts, go to next step. If IAT2 PID voltage is 
4 volts or less, replace PCM. 

33) Simulate Low IAT2 Voltage Signal 
 
Ensure ignition switch is turned to ON position. Monitor IAT2 PID voltage while connecting jumper wire 
between IAT2 and SIG RTN circuits at IAT2 sensor harness connector. If IAT2 PID voltage is one volt 
or more, replace PCM. If IAT2 PID voltage is less than one volt, reconnect IAT2 sensor. Road test 
vehicle under operate vehicle under conditions listed in appropriate PIN VOLTAGE/PID VALUE - 
INPUTS chart in appropriate PIN VOLTAGE/PID VALUE CHARTS article. Compare PID values from 
road test to IAT2 PID values in PIN VOLTAGE/PID VALUE - INPUTS chart. If IAT2 sensor is not 
within specification for each condition, replace IAT2 sensor.  

TEST DV: ELECTRONIC THROTTLE CONTROL THROTTLE POSITION SENSOR, THROTTLE 
CONTROL MOTOR 

Description 

The normal range of the throttle angle measurement for the ETC Throttle Position (TP) sensor is 0 to 83 
degrees. For voltage range, see Fig. 216. 

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