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Test J: No Module/Network Communication - ISO 9141 Network

  1. Turn ignition switch to LOCK position. Disconnect Central Timer Module (CTM) harness connector C1000. See Figure . Measure resistance between DLC terminal No. 7 (White/Black wire) and CTM harness connector C1000 terminal No. 20. See Figure and Figure . If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair circuit between DLC and CTM. See WIRING DIAGRAMS  .
  2. Reconnect CTM harness connector C1000. Measure resistance between ground and DLC terminal No. 7 (White/Black wire). If resistance is more than 10 k/ohms, go to step  10 . If resistance is 10 k/ohms or less, go to next step.
  3. Disconnect Gray 40-pin in-line harness connector C70. Measure resistance between ground and DLC terminal No. 7 (White/Black wire). If resistance is more than 10 k/ohms, go to step  9 . If resistance is 10 k/ohms or less, go to next step.
  4. Disconnect Central Junction Box (CJB) harness connector C15. See Figure . Measure resistance between ground and DLC terminal No. 7 (White/Black wire). If resistance is more than 10 k/ohms, go to next step. If resistance is 10 k/ohms or less, go to step  6 .
  5. Disconnect CTM harness connector C1000. Measure resistance between ground and CTM harness connector C1000 terminal No. 20. See Figure . If resistance is more than 10 k/ohms, go to step  16 . If resistance is 10 k/ohms or less, repair or replace CJB and retest system.
  6. Disconnect Central Security Module (CSM) harness connector C452. Measure resistance between ground and DLC terminal No. 7 (White/Black wire). If resistance is more than 10 k/ohms, go to step  17 . If resistance is 10 k/ohms or less, go to next step.
  7. Disconnect Restraint Control Module (RCM) harness connector C424. Measure resistance between ground and DLC terminal No. 7 (White/Black wire). If resistance is more than 10 k/ohms, go to step  18 . If resistance is 10 k/ohms or less, go to next step.
  8. Reconnect Gray 40-pin in-line harness connector C70. Disconnect ABS control module harness connector C385. Measure resistance between ground and DLC terminal No. 7 (White/Black wire). If resistance is more than 10 k/ohms, go to step  19 . If resistance is 10 k/ohms or less, go to next step.
    9. NOTE: When ignition switch is in RUN position, normal voltage between ground and DLC terminal No. 7 is about 1.5 volts less than battery voltage if circuit is not carrying data.
  9. Reconnect CTM harness connector C1000. Turn ignition switch to RUN position. Measure voltage between ground and DLC terminal No. 7 (White/Black wire). If battery voltage exists, go to next step. If battery voltage does not exist, perform data link diagnostic test. See DATA LINK DIAGNOSTIC TEST  under SELF-DIAGNOSTIC SYSTEM.
  10. Turn ignition switch to LOCK position. Disconnect Gray 40-pin in-line harness connector C70. Turn ignition switch to RUN position. Measure voltage between ground and DLC terminal No. 7 (White/Black wire). If battery voltage exists, go to next step. If battery voltage does not exist, go to step  15 .
  11. Turn ignition switch to LOCK position. Disconnect CJB harness connector C15. See Figure . Turn ignition switch to RUN position. Measure voltage between ground and DLC terminal No. 7 (White/Black wire). If battery voltage exists, go to step  13 . If battery voltage does not exist, go to next step.
  12. Turn ignition switch to LOCK position. Disconnect CTM harness connector C1000. Reconnect CJB harness connector C15. Turn ignition switch to RUN position. Measure voltage between ground and DLC terminal No. 7 (White/Black wire). If battery voltage exists, repair or replace CJB and retest system. If battery voltage does not exist, go to step  16 .
  13. Turn ignition switch to LOCK position. Disconnect CSM harness connector C452. Turn ignition switch to RUN position. Measure voltage between ground and DLC terminal No. 7 (White/Black wire). If battery voltage exists, go to next step. If battery voltage does not exist, go to step  17 .
  14. Turn ignition switch to LOCK position. Disconnect RCM harness connector C424. Turn ignition switch to RUN position. Measure voltage between ground and DLC terminal No. 7 (White/Black wire). If battery voltage exists, go to next step. If battery voltage does not exist, go to step  18 .
  15. Turn ignition switch to LOCK position. Reconnect Gray 40-pin in-line harness connector C70. Disconnect ABS control module harness connector C385. Turn ignition switch to RUN position. Measure voltage between ground and DLC terminal No. 7 (White/Black wire). If battery voltage exists, repair short to voltage in circuit between DLC and ABS control module. Perform data link diagnostic test. See DATA LINK DIAGNOSTIC TEST  under SELF-DIAGNOSTIC SYSTEM. If battery voltage does not exist, go to step  19 .
  16. Inspect CTM harness connector C1000 for loose, damaged or corroded terminals. Repair as necessary. Reconnect all harness connectors and retest system. If symptom still exists, replace CTM and repeat data link diagnostic test. See DATA LINK DIAGNOSTIC TEST  under SELF-DIAGNOSTIC SYSTEM. If symptom does not exist, system is okay at this time. Clear DTCs and repeat self-test.
  17. Inspect CSM harness connector C452 for loose, damaged or corroded terminals. Repair as necessary. Reconnect all harness connectors and retest system. If symptom still exists, replace CSM and repeat data link diagnostic test. See DATA LINK DIAGNOSTIC TEST  under SELF-DIAGNOSTIC SYSTEM. If symptom does not exist, system is okay at this time. Clear DTCs and repeat self-test.
  18. Inspect RCM harness connector C424 for loose, damaged or corroded terminals. Repair as necessary. Reconnect all harness connectors and retest system. If symptom still exists, replace RCM and repeat data link diagnostic test. See DATA LINK DIAGNOSTIC TEST  under SELF-DIAGNOSTIC SYSTEM. If symptom does not exist, system is okay at this time. Clear DTCs and repeat self-test.
  19. Inspect ABS control module harness connector C385 for loose, damaged or corroded terminals. Repair as necessary. Reconnect all harness connectors and retest system. If symptom still exists, replace ABS control module and repeat data link diagnostic test. See DATA LINK DIAGNOSTIC TEST  under SELF-DIAGNOSTIC SYSTEM. If symptom does not exist, system is okay at this time. Clear DTCs and repeat self-test.
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