Starting System: Diagnosis Ford Expedition II

TROUBLE SHOOTING

Check battery charge. Check cable connections at battery and starter motor. Ensure transmission is fully engaged in Park or Neutral. Check central junction box fuses No. 101 (30-amp) and No. 102 (30-amp). On models equipped Passive Anti-Theft System (PATS), ensure the PATS is operating properly. See appropriate PASSIVE ANTI-THEFT SYSTEMS article in ACCESSORIES & EQUIPMENT for additional information. If problem exists, repair as necessary. If problem does not exist, repair by symptom. See SYMPTOM INDEX table under SYSTEM TESTS.

TEST A: ENGINE DOES NOT CRANK OR RELAY CLICKS

1. Check battery condition. Battery voltage should be 12 volts or more. Load test battery at approximately one-half cold cranking amperage rating. See load tester manufacturer's instructions. If battery is okay, go to next step. If battery voltage is less than 12 volts or battery voltage is less than 9.6 volts when loaded, service or replace battery as necessary.
2. Measure voltage between negative battery cable connection at engine block and positive battery post. If voltage is greater than 10 volts, go to next step. If voltage is less than 10 volts, replace negative battery cable. Retest system for normal operation.
3. Measure voltage between starter motor case and positive battery post. If voltage is greater than 10 volts, go to next step. If voltage is less than 10 volts, clean starter motor mounting flange and ensure starter motor is properly installed. Retest system for normal operation.
4. Turn ignition switch to LOCK position. Measure voltage between ground and starter solenoid terminal "B". (Scheme 1) If voltage is greater than 10 volts, go to next step. If voltage is less than 10 volts, replace positive battery cable. Retest system for normal operation.
5. Connect a remote starter switch between starter solenoid terminal "B" (positive battery cable connection) and "S" (Red wire). (Scheme 1) Engage remote starter switch. If starter engages and cranks engine, go to next step. If starter motor does not engage and crank engine, replace starter motor. See «STARTER MOTOR»(ref-168318-S04282325992004110400000) under REMOVAL & INSTALLATION. Retest system for normal operation.
6. Disconnect starter solenoid terminal "S" (Yellow/Light Blue wire). (Scheme 1) Measure voltage between ground and starter solenoid harness connector terminal "S" (Yellow/Light Blue wire) with ignition switch in START position. If voltage is less than 10 volts, go to next step. If voltage is greater than 10 volts, clean the starter solenoid "S" terminal and connector. Check the wiring and the starter motor for a loose or intermittent connection. Test the system for normal operation.
7. Disconnect the starter relay. Place the transmission range selector in Park or Neutral. Hold the ignition switch in the START position. Measure the voltage between the starter relay cavity No. 86 (Tan/Red wire) and ground. (Scheme 2) If voltage is greater than 10 volts, go to next step. If voltage is less than 10 volts, go to step 14.
8. Turn ignition switch to START position. Measure voltage between starter relay cavity No. 85 (Dark Blue/Orange wire) and starter relay cavity 86 (Tan/Red wire). (Scheme 2) If voltage is less than 10 volts, go to next step. If voltage is greater than 10 volts, go to step 11.
9. Turn ignition to the OFF position. Disconnect Powertrain Control Module (PCM) connector C175b. Measure resistance between PCM connector C175b terminal No. 4 (Dark Blue/Orange wire) and starter relay cavity No. 85. (Scheme 2)and (Scheme 3). If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or greater, repair circuit between starter relay and PCM connector C175b. See «WIRING DIAGRAMS»(ref-168318-S10789785922004110400000). Test the system for normal operation.
10. With Powertrain Control Module (PCM) connector C175b disconnected, turn ignition to the ON/RUN position. Measure voltage between ground and starter relay cavity No. 85. (Scheme 2) If voltage is greater than 10 volts, repair Dark Blue/Orange wire between starter relay and PCM connector C175b. See «WIRING DIAGRAMS»(ref-168318-S10789785922004110400000). Test the system for normal operation. If voltage is less than 10 volts, the concern is in the Passive Anti-Theft System (PATS). See appropriate ANTI-THEFT SYSTEMS article in ACCESSORIES & EQUIPMENT.
11. Turn ignition to OFF position. Measure voltage between ground and starter relay cavity 30. (Scheme 2) If voltage is greater than 10 volts, go to next step. If voltage is less than 10 volts, repair power distribution circuit. See «WIRING DIAGRAMS»(ref-168318-S10789785922004110400000). Test the system for normal operation.
12. With ignition in OFF position and starter solenoid terminal "S" (Yellow/Light Blue wire) disconnected. Measure the resistance between starter relay cavity 87 (Yellow/Light Blue wire) and ground. (Scheme 2) If the resistance is greater than 10k ohms, go to next step. If resistance is less than 10k ohms, repair Yellow/Light Blue wire between starter motor and starter relay. See «WIRING DIAGRAMS»(ref-168318-S10789785922004110400000). Test the system for normal operation.
13. Measure resistance between starter solenoid terminal "S" (Yellow/Light Blue wire) and starter relay cavity 87. (Scheme 2) If resistance is less than 5 ohms, install a new starter relay. Test the system for normal operation. If resistance is 5 ohms or greater, repair Yellow/Light Blue wire between starter motor and starter relay. See «WIRING DIAGRAMS»(ref-168318-S10789785922004110400000). Test the system for normal operation.
14. Disconnect Digital Transmission Range (DTR) sensor connector. Measure the resistance of (Tan/Red wire) between the starter relay cavity 86 and the DTR sensor connector terminal No. 12. (Scheme 2)and (Scheme 4). If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or greater, repair Tan/Red wire between starter relay and DTR sensor connector. See «WIRING DIAGRAMS»(ref-168318-S10789785922004110400000). Test the system for normal operation.
15. Turn ignition switch to ON/RUN position. Measure the voltage between the Digital Transmission Range (DTR) sensor connector terminal No. 10 (White/Pink wire) and ground. (Scheme 4) If the voltage is less than 10 volts, go to next step. If the voltage is greater than 10 volts, adjust DTR sensor. See «DIGITAL TRANSMISSION RANGE SENSOR»(ref-168318-S35428242952004110400000) under ADJUSTMENTS. If concern still exists, replace the DTR sensor. Retest for normal operation.
16. With ignition in OFF position, disconnect central junction box connector C270d. Measure resistance between Digital Transmission Range (DTR) sensor connector terminal No 10 (White/Pink wire) and central junction box connector C270d terminal No. 1 (White/Pink wire). (Scheme 4)and (Scheme 6). If resistance is less than 5 ohms, go to next step. If resistance is greater than 5 ohms, repair White/Pink wire between central junction box and DTR sensor connector. See «WIRING DIAGRAMS»(ref-168318-S10789785922004110400000). Retest for normal operation.
17. With ignition in OFF position, disconnect ignition switch harness connector and central junction box connector C270h. Measure the resistance between ignition switch connector terminal No. 7 (Red/Light Blue wire) and central junction box connector C270h terminal No. 11 (Red/Light Blue wire). (Scheme 5)and (Scheme 6). If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or greater, repair Red/Light Blue wire between central junction box and ignition switch connector. See «WIRING DIAGRAMS»(ref-168318-S10789785922004110400000). Retest for normal operation.
18. Turn ignition switch to ON/START position. Measure voltage between ignition switch connector terminal No. 4 (Light Green/Violet wire) and ground. (Scheme 5) If voltage is greater than 10 volts, install a NEW ignition switch. See appropriate STEERING COLUMN SWITCHES article in ACCESSORIES & EQUIPMENT. Retest for normal operation. If voltage is less than 10 volts, repair Light Green/Violet wire between central junction box connector C270g and ignition switch connector. See «WIRING DIAGRAMS»(ref-168318-S10789785922004110400000). Retest for normal operation.

Scheme 1

Scheme 2

Scheme 3

Scheme 4

Scheme 5

Scheme 6

TEST B: UNUSUAL STARTER NOISE

1. Verify starter is installed properly. Ensure bolts are tight. If starter is mounted properly, go to next step. If problem exists, repair as necessary and check system for normal operation.
2. Connect a remote starter switch between starter solenoid terminal "B" (positive battery cable connection) and terminal "S" (Red wire). (Scheme 1) Engage starter motor and verify noise is coming from starter motor. If noise is coming from starter motor, go to next step. If noise is not coming from starter motor, diagnose engine mechanical problem. See appropriate article in ENGINES.
3. Remove starter motor. See «STARTER MOTOR»(ref-168318-S04282325992004110400000) under REMOVAL & INSTALLATION. Inspect flywheel ring gear for wear or damage. (Scheme 7) If ring gear is okay, replace starter motor. If ring gear is worn or damaged, replace ring gear and inspect starter drive gear. If drive gear is also damaged, replace starter motor. See «STARTER MOTOR»(ref-168318-S04282325992004110400000) under REMOVAL & INSTALLATION.

Scheme 7

ON-VEHICLE TESTING

VOLTAGE DROP TEST

Note. Make all DVOM connections at component terminal rather than at cable or wire end. Clean all connections at starter and battery before beginning this test.

1. Verify battery condition. Battery voltage should be 12 volts or more. Load test battery at approximately one-half cold cranking amperage rating. See load tester manufacturer's instructions. If battery is okay, go to next step. If battery voltage is less than 12 volts or loaded battery voltage is less than 9.6 volts, service or replace battery as necessary.
2. Disconnect inertia fuel shutoff switch harness connector. Inertia fuel shutoff switch is located behind left rear quarter trim panel. Connect remote starter switch between starter solenoid terminal "S" and positive battery post. Using DVOM, connect Red lead to positive battery post and Black lead to solenoid terminal "M". (Scheme 8) Engage remote starter switch. If DVOM indicates more than.5 volt, go to next step. If DVOM indicates.5 volt or less, go to «STARTER GROUND CIRCUIT TEST»(ref-168318-S06199954182004110400000).
3. Move Black lead to solenoid terminal "B". Engage remote starter switch. If DVOM indicates more than.5 volt, go to next step. If DVOM indicates.5 volt or less, solenoid connections or contacts are bad. Clean solenoid terminals "B", "S" and "M". Repeat steps 1) and 2). If DVOM still indicates more than.5 volt at terminal "M" and.5 volt or less at terminal "B", replace starter motor. See «STARTER MOTOR»(ref-168318-S04282325992004110400000) under REMOVAL & INSTALLATION.
4. Clean cables and connections at solenoid. If DVOM still indicates more than.5 volt at terminal "B", check for poor positive battery cable connection or bad cable. To locate excessive voltage drop, move DVOM Black lead toward battery, and check each connection point. When high DVOM reading disappears, last connection point checked is cause of problem. Repair or replace as necessary.

Scheme 8

STARTER GROUND CIRCUIT TEST

Note. Make all DVOM connections at component terminal rather than at cable or wire end.

Scheme 9

1. Disconnect inertia fuel shutoff switch harness connector. Inertia fuel shutoff switch is located behind left rear quarter trim panel. Connect remote starter switch between starter solenoid terminal "S" and positive battery post. Using DVOM, connect Red lead to starter housing, and Black lead to negative battery post. (Scheme 9) Engage remote starter switch while observing DVOM. If voltage is more than.2 volt, leave test equipment attached and go to next step. If voltage is.2 volt or less, starter ground circuit is okay at this time.
2. Clean negative cable connections at battery and chassis. Engage remote starter switch while observing DVOM. If voltage is more than.2 volt, leave test equipment attached and go to next step. If voltage is.2 volt or less, starter ground circuit is okay at this time.
3. Connect DVOM between negative battery post and engine ground where negative battery cable connects. Engage remote starter switch while observing DVOM. If voltage is more than.2 volt, replace negative battery cable. If voltage is.2 volt or less and the engine cranks slowly, replace starter motor. See «STARTER MOTOR»(ref-168318-S04282325992004110400000) under REMOVAL & INSTALLATION.