Ford F150 Pickup. Instruction - part 692

Fig. 9: Identifying Central Junction Box Connector C270a & C270b Terminals 
Courtesy of FORD MOTOR CO. 

15. Momentarily turn ignition switch to START position. Turn ignition switch to LOCK position. Remove 

 

2003 Ford Pickup F150 

2003 STARTING & CHARGING SYSTEMS Starters - F150 Pickup

  

fuse No. 111 (40-amp) from battery junction box. Check fuse for open. If fuse is open, go to next step. If 
fuse is okay, system is okay at this time.  

16. Disconnect ignition switch connector. Measure resistance between ground and ignition switch connector 

terminal B5 (Light Green/Violet wire). See Fig. 6 . If resistance is greater than 10 k/ohms, go to next step. 
If resistance is 10 k/ohms or less, repair short to ground in Light Green/Violet wire between ignition 
switch and battery junction box. See WIRING DIAGRAMS .  

17. Remove fuse No. 21 (15-amp) from central junction box. Measure resistance between ground and ignition 

switch connector terminal STA (Red/Light Blue wire). See Fig. 6 . If resistance is greater than 10 k/ohms, 
replace ignition switch. Check system operation. If resistance is 10 k/ohms or less, repair short to ground 
in Red/Light Blue wire between ignition switch and central junction box. See 

WIRING DIAGRAMS

 .  

18. Turn ignition switch to START position. Turn ignition switch to LOCK position. Remove and recheck 

fuse No. 21. If fuse is not open, no problem is indicated at this time. If fuse is open, install new fuse and 
go to next step.  

19. Disconnect starter motor relay connectors. Turn ignition switch to START position. Turn ignition switch 

to LOCK position. Recheck fuse No. 21. If fuse is okay, replace starter motor relay. Check system 
operation. If fuse is open, install new fuse and go to next step.  

20. Disconnect CPP switch or CPP jumper connector. Measure resistance between ground and CPP 

switch/jumper connector terminal No. 1 (White/Pink wire). See Fig. 8 . If resistance is greater than 10 
k/ohms, go to next step (A/T) or go to step 24 (M/T). If resistance is less than 10 k/ohms, repair short to 
ground in White/Pink wire between CPP switch/jumper and central junction box. See WIRING 
DIAGRAMS . Check system operation.  

21. Place transmission in Park. Measure resistance between ground and Tan/Red wire at starter motor relay 

connector terminal . If resistance is 10 k/ohms or less, go to next step. If resistance is greater than 10 
k/ohms, replace CPP jumper. Check system operation.  

22. Disconnect DTR sensor connector. Measure resistance between ground and DTR sensor connector 

terminal No. 10 (Dark Blue/Orange wire). See Fig. 7 . If resistance is greater than 10 k/ohms, go to next 
step. If resistance is 10 k/ohms or less, repair short to ground in Dark Blue/Orange wire between DTR 
sensor and CPP jumper. See WIRING DIAGRAMS . Check system operation.  

23. Disconnect starter motor relay connector (Tan/Red wire). Measure resistance between ground and DTR 

sensor connector terminal No. 12 (Tan/Red wire). If resistance is greater than 10 k/ohms, replace DTR 
sensor. Check system operation. If resistance is 10 k/ohms or less, repair short to ground in Tan/Red wire 
between DTR sensor and starter motor relay. See WIRING DIAGRAMS . Check system operation.  

24. Disconnect starter motor relay connector (Tan/Red wire). Measure resistance between ground and CPP 

switch connector terminal No. 2 (Dark Blue/Orange wire). See Fig. 8 . If resistance is greater than 10 
k/ohms, replace CPP switch. Check system operation. If resistance is 10 k/ohms or less, repair short to 
ground in Tan/Red wire between CPP switch and starter motor relay. See WIRING DIAGRAMS . 
Check system operation.  

TEST C: ENGINE CRANKS SLOWLY 

1. Turn ignition switch to LOCK position. Check voltage between starter motor solenoid positive terminal 

"B" and ground. See Fig. 5 . If battery voltage is present, go to next step. If battery voltage is not present, 
clean and tighten connections. If battery voltage is still not present, repair or replace positive battery 
cable. Check system operation.  

2. Perform starter ground circuit test. See STARTER GROUND CIRCUIT TEST under ON-VEHICLE 

 

2003 Ford Pickup F150 

2003 STARTING & CHARGING SYSTEMS Starters - F150 Pickup

  

TESTING. If ground circuit is okay, replace starter motor. See STARTER MOTOR under REMOVAL 
& INSTALLATION. Check system operation. If ground circuit is not okay, repair ground circuit as 
necessary. Check system operation.  

TEST D: UNUSUAL STARTER NOISE 

1. Verify starter is installed properly. Check brackets for cracks. Ensure bolts are tight. Repair or replace as 

necessary. Check system for normal operation. If noise is still present, go to next step.  

2. Remove starter motor. See STARTER MOTOR under REMOVAL & INSTALLATION. Inspect starter 

motor and flywheel ring gear for wear or damage. If ring gear is worn or damaged, replace ring gear and 
inspect starter drive gear. If drive gear is also damaged, replace starter motor. If ring gear and starter 
motor are okay, perform STARTER NO-LOAD TEST under BENCH TESTING. Repair or replace as 
necessary.  

 

2003 Ford Pickup F150 

2003 STARTING & CHARGING SYSTEMS Starters - F150 Pickup

  

Fig. 10: Identifying Starter Drive Gear & Flywheel Ring Gear 
Courtesy of FORD MOTOR CO. 

ON-VEHICLE TESTING 

VOLTAGE DROP TEST 

CAUTION: When battery is disconnected, vehicle computer and memory systems 

may lose memory data. Driveability problems may exist until computer 
systems have completed a relearn cycle. See COMPUTER RELEARN 
PROCEDURES article in GENERAL INFORMATION before disconnecting 
battery. Before testing starter, ensure transmission is in Park or Neutral.

 

2003 Ford Pickup F150 

2003 STARTING & CHARGING SYSTEMS Starters - F150 Pickup