Ford F150 Pickup. Instruction - part 1494

14) Check For PCM BPA PID Cycling 
Start engine and allow to idle. Using scan tool, access BPA PID from PID/DATA MONITOR & 
RECORD menu. Apply and release brake pedal several times while monitoring BPA PID. If BPA PID 
cycles ON and OFF, go to next step. If BPA PID does not cycle ON and OFF, go to step 11). 

15) BPP & BPA Switch Rationality Check 
 
Reconnect all disconnected components. Clear DTCs. See CLEARING CODES under SELF-
DIAGNOSTIC SYSTEM. Start engine and allow to idle. Apply and release brake pedal several times. 
Perform CONTINUOUS MEMORY SELF-TEST. If P1572 is still present, check for misadjusted BPP 
or BPA switch. Service as necessary. If DTC P1572 is no longer present, go to next step. 

16) Check PCM For Reoccurring BPP DTCS 
 
Re-run KOER Self-test. Retrieve Continuous Memory DTCs. If DTC P0703 or P1703 is present, replace 
PCM. If DTC P0703 or P1703 is not present, test is complete.  

TEST FF: POWER STEERING PRESSURE SWITCH 

Diagnostic Aids 

Perform this test when instructed during QUICK TEST or if directed by other test procedures. Some vehicles 
may not have power steering, but PCM may be equipped with PSP switch software strategy. If a KOEO DTC 
P1650 or P1651 is displayed, ensure vehicle is equipped with power steering. If vehicle is not equipped with 
power steering, disregard DTC P1650 or P1651. This test is only intended to diagnose:  

z

PSP Switch  

z

Wiring Harness Circuits (PSP & SIG RTN)  

z

Powertrain Control Module (PCM)  

NOTE:

If BPA PID is not accessible with scan tool in this test step, go to step 11).

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

  

Fig. 228: Identifying PSP Switch Circuits & Connector Terminals (Focus) 
Courtesy of FORD MOTOR CO. 

 

2003 Ford Pickup F150 

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

  

Fig. 229: Identifying PSP Switch Circuits & Connector Terminals (All Others) 
Courtesy of FORD MOTOR CO. 

Testing 

NOTE:

For additional testing information, see DIAGNOSTIC AIDS.

NOTE:

If DTC P1650 was received in KOER self-test, ensure steering wheel was 
turned at least a 1/2 turn within 20 seconds of starting self-test.

 

2003 Ford Pickup F150 

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

  

1) For KOEO & KOER Only DTC P1650: Check PSP PID 
DTC P1650 indicates PSP signal input to PCM was high when retrieved during KOEO on-demand self-
test. DTC P1650 indicates PSP signal input to PCM did not change state when retrieved during KOER 
on-demand self-test. Possible causes for these faults are: 

z

Steering Wheel Was Not Turned During KOER ON-DEMAND SELF-TEST  

z

Faulty PSP Switch/Shorting Bar Damage  

z

SIG RTN Circuit Open  

z

PSP Circuit Open Or Shorted To SIG RTN  

z

Faulty Powertrain Control Module (PCM)  

Connect scan tool to Data Link Connector (DLC). Start engine and allow to idle. Using scan tool, access 
PSP PID from PID/DATA MONITOR & RECORD menu. Observe PSP PID and turn steering wheel to 
the left, then to the right. If PSP PID value does not indicate a change, go to next step. If PSP PID value 
indicates a change, go to step 10). 

2) Check For PSP Circuits To PSP Switch For Cycling 
 
Turn ignition switch to OFF position. Remove shorting bar or disconnect connector from PSP switch. 
Install a jumper wire between PSP switch harness connector terminals. Start engine and allow to idle. 
Record PSP PID value. Disconnect jumper wire and again record PSP PID value. If PSP PID value 
changed from low to high, replace PSP switch. If PSP PID value did not change as specified, go to next 
step (Focus), or go to step 4) (all others). 

3) Check For Open GND Circuit To PSP Switch 
 
Turn ignition switch to OFF position. Using a DVOM, measure resistance of PSP circuit between PSP 
sensor harness connector and chassis ground. See Fig. 228. If resistance measurement is less than 5 ohms, 
go to next step. If resistance measurement is 5 ohms or more, repair open in PSP circuit. 

4) Check PSP & SIG RTN Circuits For Open In Harness 
 
Ensure ignition switch is in OFF position. Disconnect PCM connector(s). On all models, use a DVOM 
and measure resistance of PSP circuit between PCM harness connector and PSP switch harness 
connector. On all models except Focus, use a DVOM and measure resistance of SIG RTN circuit between 
PCM harness connector and PSP switch harness connector. See Fig. 228 or Fig. 229 . If all resistance 
measurements are less than 5 ohms, go to next step. If any resistance measurement is 5 ohms or more, 
repair open in PSP or SIG RTN circuit. 

5) Check PSP Circuit For Short To SIG RTN Or Ground In Harness 
 
On all models, use a DVOM and measure resistance between PSP circuit at PSP switch harness connector 
and chassis ground. On all models except Focus, use a DVOM and measure resistance between PSP and 
SIG RTN circuits at PSP switch harness connector. See Fig. 228 or Fig. 229 . If all resistance 
measurements are more than 10 k/ohms, replace PCM. If either resistance measurement is 10 k/ohms or 
less, repair short to ground or between affected circuits. 

 

2003 Ford Pickup F150 

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