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DTC U2004: Transmitted SPI Data Output Low: Testing

  1. If body function controller (BFC) diagnostic system check has been performed, go to next step. If body function controller (BFC) diagnostic system check has not been performed, go toBODY FUNCTION CONTROLLER (BFC) DIAGNOSTIC SYSTEM CHECK  under SYSTEM TESTS.
  2. Disconnect BFC Pink 24-pin connector C3. Turn ignition switch to RUN position. Using DVOM, measure voltage at BFC connector C3 terminal A3 (Yellow wire). If battery voltage exists, go to next step. If battery voltage does not exist, go to step  6 .
  3. Check for a poor connection at BFC connector C3 terminal A3 (Yellow wire). If a poor connection exists, go to next step. If connection is okay, go to step  5 .
  4. Repair poor connection at BFC connector C3 terminal A3 (Yellow wire). After repairs, go to step  13 .
  5. Replace BFC. See BODY FUNCTION CONTROLLER (BFC)  under REMOVAL & INSTALLATION. After repairs, go to step  13 .
  6. Disconnect IPC Gray 24-pin connector. Using DVOM, measure resistance in Yellow wire between BFC connector C3 terminal A3 and IPC connector terminal A9. See Figure . If resistance is 0-2 ohms, go to next step. If resistance is not 0-2 ohms, go to step  8 .
  7. Using DVOM, measure resistance between BFC connector C3 terminal A3 (Yellow wire) and ground. If continuity is not indicated, go to step  10 . If continuity is indicated, go to step  9 .
  8. Repair open in Yellow wire between BFC and IPC. After repairs, go to step  13 .
  9. Repair short to ground in Yellow wire between BFC and IPC. After repairs, go to step  13 .
  10. Check for a poor connection at IPC connector terminal A9 (Yellow wire). If a poor connection exists, go to next step. If connection is okay, go to step  12 .
  11. Repair poor connection at IPC connector terminal A9 (Yellow wire). After repairs, go to step  13 .
  12. Replace IPC. See appropriate ANALOG INSTRUMENT PANELS article. After repairs, go to next step.
  13. Reconnect all disconnected components and connectors. Clear DTCs. Perform BODY FUNCTION CONTROLLER (BFC) DIAGNOSTIC SYSTEM CHECK  under SYSTEM TESTS.
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