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

NOTE: Depending on module configuration, with all modules connected and with ignition switch in RUN position or with engine running, 2-3 volts may exist at Data Link Connector (DLC) terminal No. 7 (White wire without ABS; White/Blue wire with ABS). This is the International Standards Organization (ISO) 9141 diagnostic communications network circuit.
NOTE: Anti-theft/double locking module may also be referred to as Central Security Module (CSM). Hybrid Electronic Cluster (HEC) module is built into instrument cluster. Air bag control module may also be referred to as electronic crash sensor module.
  1. Turn ignition switch to LOCK position. Disconnect NGS tester (if connected). Disconnect 14-pin in-line harness connector C62, located behind instrument cluster. Inspect connector for loose, damaged or corroded terminals. If connector is damaged, repair connector as necessary. Check resistance between male side of in-line harness connector C62 terminal No. 6 (White wire) and DLC terminal No. 7 (White wire without ABS; White/Blue wire with ABS). See Figure and Figure . If resistance is 5 ohms or less, go to next step. If resistance is more than 5 ohms, repair open in White wire and/or White/Blue wire between DLC and in-line harness connector C62.
  2. Connect in-line harness connector C62. Turn ignition switch to RUN position. Check voltage between ground and DLC terminal No. 7 (White wire without ABS; White/Blue wire with ABS). If battery voltage exists, go to next step. If battery voltage does not exist, go to step  12 .
  3. Turn ignition switch to LOCK position. Disconnect 14-pin in-line harness connector C62, located behind instrument cluster. Turn ignition switch to RUN position. Check voltage between ground and DLC terminal No. 7 (White wire without ABS; White/Blue wire with ABS). If battery voltage exists, go to next step. If battery voltage does not exist, go to step  5 .
  4. Turn ignition switch to LOCK position. Disconnect ABS module harness connector C385. Turn ignition switch to RUN position. Check voltage between ground and DLC terminal No. 7 (White wire without ABS; White/Blue wire with ABS). If battery voltage exists, repair short to voltage on White wire (without ABS) or White/Blue wire (with ABS). If battery voltage does not exist, replace ABS module.
  5. If vehicle is equipped with an anti-theft/double locking module, go to next step. If vehicle is not equipped with an anti-theft/double locking module, go to step  10 .
  6. Turn ignition switch to LOCK position. Disconnect 16-pin in-line harness connector C58, located in passenger's side kick panel. Turn ignition switch to RUN position. Check voltage between ground and female side of in-line harness connector C62 terminal No. 6 (White wire). If battery voltage exists, go to next step. If battery voltage does not exist, go to step  9 .
  7. Turn ignition switch to LOCK position. Disconnect air bag control module harness connector C20. Turn ignition switch to RUN position. Check voltage between ground and female side of in-line harness connector C62 terminal No. 6 (White wire). If battery voltage exists, go to next step. If battery voltage does not exist, replace air bag control module.
  8. Turn ignition switch to LOCK position. Disconnect Hybrid Electronic Cluster (HEC) module harness connector C808a. Turn ignition switch to RUN position. Check voltage between ground and female side of in-line harness connector C62 terminal No. 6 (White wire). If battery voltage exists, repair short to voltage on ISO circuit. See DATA LINK CONNECTORS article in WIRING DIAGRAMS. If battery voltage does not exist, replace instrument cluster.
  9. Turn ignition switch to LOCK position. Disconnect anti-theft/double locking module harness connector C451b, located in passenger's side kick panel. Turn ignition switch to RUN position. Check voltage between ground and male side of in-line harness connector C58 terminal No. 9 (White wire). If battery voltage exists, repair short to voltage on White wire between in-line harness connector C58 and anti-theft/double locking module. If battery voltage does not exist, replace anti-theft/double locking module.
  10. Turn ignition switch to LOCK position. Disconnect air bag control module harness connector C20. Turn ignition switch to RUN position. Check voltage between ground and female side of in-line harness connector C62 terminal No. 6 (White wire). If battery voltage exists, go to next step. If battery voltage does not exist, replace air bag control module.
  11. Turn ignition switch to LOCK position. Disconnect Hybrid Electronic Cluster (HEC) module harness connector C808a. Turn ignition switch to RUN position. Check voltage between ground and female side of in-line harness connector C62 terminal No. 6 (White wire). If battery voltage exists, repair short to voltage on ISO circuit. See DATA LINK CONNECTORS article in WIRING DIAGRAMS. If battery voltage does not exist, replace instrument cluster.
  12. Turn ignition switch to LOCK position. Check resistance between ground and terminal No. 7 (White wire without ABS; White/Blue wire with ABS) at DLC. If resistance is 10 k/ohms or less, go to next step. If resistance is more than 10 k/ohms, ISO circuit is okay. Recheck system.
  13. Disconnect 14-pin in-line harness connector C62, located behind instrument cluster. Check resistance between ground and DLC terminal No. 7 (White wire without ABS; White/Blue wire with ABS). If resistance is 10 k/ohms or less, go to next step. If resistance is more than 10 k/ohms, go to step  16 .
  14. If vehicle is equipped with ABS, go to next step. If vehicle is not equipped with ABS, repair White wire between DLC terminal No. 7 and anti-theft/double locking module terminal No. 4.
  15. Disconnect anti-lock brake module harness connector C385. Check resistance between ground and DLC terminal No. 7 (White/Blue wire). If resistance is 10 k/ohms or less, repair short to ground on White/Blue wire. If resistance is more than 10 k/ohms, replace anti-lock brake module.
  16. If vehicle is equipped with an anti-theft/double locking module, go to next step. If vehicle is not equipped with an anti-theft/double locking module, go to step  19 .
  17. Disconnect 16-pin in-line harness connector C58, located in passenger's side kick panel. Check resistance between ground and female side of in-line harness connector C62 terminal No. 6 (White wire). If resistance is more than 10 k/ohms, go to next step. If resistance is 10 k/ohms or less, go to step  19 .
  18. Disconnect anti-theft/double locking module harness connector C451b, located in passenger's side kick panel. Check resistance between ground and male side of in-line harness connector C58 terminal No. 9 (White wire). If resistance is more than 10 k/ohms, replace anti-theft/double locking module. If resistance is 10 k/ohms or less, repair short to ground on White wire between anti-theft/double locking module and in-line harness connector C58. If resistance is more than 10 k/ohms, replace anti-theft/double locking module.
  19. Disconnect air bag control module harness connector C20. Check resistance between ground and female side of in-line harness connector C62 terminal No. 6 (White wire). If resistance is more than 10 k/ohms, replace air bag control module. If resistance is 10 k/ohms or less, go to next step.
  20. Disconnect Hybrid Electronic Cluster (HEC) module harness connector C808a. Check resistance between ground and terminal female side of in-line harness connector C62 No. 6 (White wire). If resistance is more than 10 k/ohms, replace Hybrid Electronic Cluster (HEC) module. If resistance is 10 k/ohms or less, repair short to ground on ISO circuit. See DATA LINK CONNECTORS article in WIRING DIAGRAMS.
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