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