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Test M: No Module/Network Communication - Bus Link

  1. Inspect NGS tester connector for loose, damaged or corroded terminals. Repair connector as necessary and retest system for normal operation. If connector is okay, go to next step.
  2. Turn ignition off. Inspect Data Link Connector (DLC) for physical damage, bent terminals or corrosion. Repair connector as necessary and retest system for normal operation. If connector is okay, go to next step.
  3. Turn ignition off. Disconnect speed control amplifier 10-pin connector located in left rear of engine compartment. Measure resistance of Tan/Orange wire between terminal No. 1 at speed control amplifier connector and terminal No. 2 at DLC. See Figure and Figure. Also, measure resistance of Pink/Light Blue wire between terminal No. 2 at speed control amplifier connector and terminal No. 10 at DLC. If both resistance readings are less than 5 ohms, go to next step. If any resistance reading is 5 ohms or more, repair open Tan/Orange wire and/or Pink/Light Blue wire between connector C201 and DLC. Retest system for normal operation.
  4. Connect NGS tester. Turn ignition on. Perform data link diagnostic procedure. See DATA LINK DIAGNOSTIC TEST under COMMUNICATION NETWORK DIAGNOSTICS. If all modules equipped on vehicle passed data link diagnostic test, except speed control amplifier, replace speed control amplifier and retest system for normal operation. If any module other than speed control amplifier did not pass data link diagnostic test, go to next step.
  5. Disconnect 76-pin connector C201 located behind left side of instrument panel. See Figure. Turn ignition on. Perform data link diagnostic procedure. See DATA LINK DIAGNOSTIC TEST under COMMUNICATION NETWORK DIAGNOSTICS. If all modules equipped on vehicle except PCM, ABS module and speed control amplifier passed data link diagnostic test, reconnect connector C201 and go to next step. If any module other than PCM, ABS module and speed control amplifier did not pass data link diagnostic test, reconnect connector C201 and go to step 8).
  6. Turn ignition off. Disconnect ABS module connector, located in right front of engine compartment, under upper radiator support. Turn ignition on. Perform data link diagnostic procedure. See DATA LINK DIAGNOSTIC TEST under COMMUNICATION NETWORK DIAGNOSTICS. If all modules equipped on vehicle except ABS module and speed control amplifier passed data link diagnostic test, replace ABS module and retest system for normal operation. If any module other than ABS module and speed control amplifier did not pass data link diagnostic test, go to next step.
  7. Turn ignition off. Disconnect PCM connector located in engine compartment on left side of firewall. Perform data link diagnostic procedure. See DATA LINK DIAGNOSTIC TEST under COMMUNICATION NETWORK DIAGNOSTICS. If all modules equipped on vehicle except ABS module, PCM and speed control amplifier passed data link diagnostic test, replace PCM and retest system for normal operation. If any module other than ABS module, PCM and speed control amplifier did not pass data link diagnostic test, repair circuit No. 914 (Tan/Orange wire) and/or circuit No. 915 (Pink/Light Blue wire) between connector C201 and ABS module, PCM, speed control amplifier and evac and fill connector C133 (Tan/Orange wire only). Retest system for normal operation.
  8. Turn ignition off. Disconnect 42-pin connector C202 located behind right side of instrument panel. See Figure. Turn ignition on. Perform data link diagnostic procedure. See DATA LINK DIAGNOSTIC TEST under COMMUNICATION NETWORK DIAGNOSTICS. If all modules equipped on vehicle except air suspension/Electronic Variable Orifice (EVO) steering module, Driver's Door Module (DDM) and Driver's Seat Module (DSM) (if equipped) passed data link diagnostic test, reconnect connector C202 and go to next step. If any module other than air suspension/EVO steering module, DDM and DSM (if equipped) did not pass data link diagnostic test, reconnect connector C202 and go to step 12).
  9. Turn ignition off. Disconnect DDM 22-pin connector C520 located inside driver's door. Turn ignition on. Perform data link diagnostic procedure. See DATA LINK DIAGNOSTIC TEST under COMMUNICATION NETWORK DIAGNOSTICS. If all modules equipped on vehicle except DDM passed data link diagnostic test, replace DDM and retest system for normal operation. If any module other than DDM did not pass data link diagnostic test, go to next step (if equipped with a DSM) or go to step 11) (if not equipped with a DSM).
  10. Turn ignition off. Disconnect DSM 26-pin connector C313 located under driver's front seat. Turn ignition on. Perform data link diagnostic procedure. See DATA LINK DIAGNOSTIC TEST under COMMUNICATION NETWORK DIAGNOSTICS. If all modules equipped on vehicle except DSM and DDM passed data link diagnostic test, replace DSM and retest system for normal operation. If any module other than DSM and DDM did not pass data link diagnostic test, go to next step
  11. Disconnect air suspension/EVO steering module Black connector C251. Connector is located below right side of instrument panel. Turn ignition on. Perform data link diagnostic procedure. See DATA LINK DIAGNOSTIC TEST under COMMUNICATION NETWORK DIAGNOSTICS. If all modules equipped on vehicle except DSM, DDM and air suspension/EVO steering module passed data link diagnostic test, replace air suspension/EVO steering module and retest system for normal operation. If any module other than DSM, DDM and air suspension/EVO steering module did not pass data link diagnostic test, repair circuit No. 914 (Tan/Orange wire) and/or circuit No. 915 (Pink/Light Blue wire) between connector C202 and DSM (if equipped), DDM and air suspension/EVO steering module and retest system for normal operation.
  12. Turn ignition off. Disconnect LCM 16-pin connector C221 located behind left side of instrument panel, right of steering column. Turn ignition on. Perform data link diagnostic procedure. See DATA LINK DIAGNOSTIC TEST under COMMUNICATION NETWORK DIAGNOSTICS. If all modules equipped on vehicle except LCM passed data link diagnostic test, replace LCM and retest system for normal operation. If any module other than LCM did not pass data link diagnostic test, go to next step (if equipped with front radio control unit) or go to step 14) (if not equipped with front radio control unit).
  13. Turn ignition off. Disconnect front radio control unit 20-pin connector C258 located behind center of instrument panel, on radio. See Figure. Turn ignition on. Perform data link diagnostic procedure. See DATA LINK DIAGNOSTIC TEST under COMMUNICATION NETWORK DIAGNOSTICS. If all modules equipped on vehicle except LCM and front radio control unit passed data link diagnostic test, replace front radio control unit and retest system for normal operation. If any module other than LCM and front radio control unit did not pass data link diagnostic test, go to next step.
  14. Turn ignition off. Disconnect instrument cluster 12-pin connector C254. Turn ignition on. Perform data link diagnostic procedure. See DATA LINK DIAGNOSTIC TEST under COMMUNICATION NETWORK DIAGNOSTICS. If all modules equipped on vehicle except instrument cluster, LCM and front radio control unit (if equipped) passed data link diagnostic test, replace instrument cluster and retest system for normal operation. If any module other than instrument cluster, LCM and front radio control unit (if equipped) did not pass data link diagnostic test, go to next step.
  15. Turn ignition off. Disconnect Electronic Automatic Temperature Control (EATC) module White connector C281 located behind center of instrument panel. Turn ignition on. Perform data link diagnostic procedure. See DATA LINK DIAGNOSTIC TEST under COMMUNICATION NETWORK DIAGNOSTICS. If all modules equipped on vehicle except EATC module, instrument cluster, LCM and front radio control unit (if equipped) passed data link diagnostic test, replace EATC module and retest system for normal operation. If any module other than EATC module, instrument cluster, LCM and front radio control unit (if equipped) did not pass data link diagnostic test, repair circuit No. 914 (Tan/Orange wire) and/or circuit No. 915 (Pink/Light Blue wire) between connector C202 and LCM, front radio control unit (if equipped), instrument cluster and EATC module. Retest system for normal operation.
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