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No Display & No Tone

  1. Close trunk and doors. Turn ignition switch to "OFF". Turn ignition switch to "ACC" while listening for tone from Message Center. If tone is detected and no display is present, proceed to step 2).
  2. Check fuel and speedometer for illumination. If lit, proceed to step 4). If not lit, proceed to step 3).
  3. Check fuse F-6. If fuse blown, service circuit 296 for short to ground. Replace fuse and repeat test. If fuse okay, proceed to step 4).
  4. Turn ignition switch to "OFF". Check for proper ground at C2-15 of Message Center control module. If ground is okay, proceed to step 5). If ground not okay, service ground circuit 57 and repeat test.
  5. Connect EIC tester to connector C-3 and turn ignition switch to "ACC". Note DVOM reading. If DVOM reads battery voltage, proceed to step 6). If no battery reading, service circuit 296 for open in circuit and repeat test.
  6. Connect tester at C-1 connector and note DVOM reading. If DVOM reads battery voltage, proceed to step 7). If no battery reading, service open in circuit 199 and repeat test.
  7. Connect tester at connector C-4 and note DVOM reading If DVOM reading is between 4.75 volts and 5.25 volts, proceed to step 10). If less than 4.75 volts, proceed to step 8). If greater than 5.25 volts, check circuit 168 for short to battery voltage. If circuit 168 is okay, replace Message Center control module and repeat test.
  8. Turn ignition switch "OFF". Disconnect C-2 connector from tester harness. Check wire 168 (White/Black) at C-2-17 of connecter for short to ground. If wire 168 is shorted, proceed to step 9). If wire is not shorted, replace Message Center control module and repeat test.
  9. Reconnect C-2 connector to tester. Disconnect connector from Message Center display module. Turn ignition switch to "ACC" and note DVOM reading. If DVOM reads between 4.75 volts and 5.25 volts, replace Message Center display module and repeat test. If reading not within limits, service wire 168 for short and repeat test.
  10. Depress Signal Simulator Display button to "ON". Press MSG button and release. Check displays. If 2 lines of characters (100000 on first line, 00000000000000 on second line) appear, replace Message Center control module, turn Signal Simulator "OFF" and then repeat test. If no display, proceed to step 11) Turn ignition switch "OFF". Check for continuity and shorts to ground on wires 168, 199, 167, 178, 174, and 192. Wire 57 should be grounded. If continuity good and no shorts exist, replace Message Center display module and repeat test. If not okay, service defective circuits or connectors and repeat test.
Fig 1: Message Center Control Module
G25461
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