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Home >> Cadillac >> 1999 >> DeVille Base >> Repair and Diagnosis >> Accessories & Equipment >> Memory Modules >> Memory System >> Memory Seat Module (MSM) Diagnostic Tests >> DTC B2111: Lumbar Down Switch Failed (Al2) Or DTC B2112: Lumbar Up Switch Failed (Al2) >> Diagnostic Procedure
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Diagnostic Procedure

  1. If power seats system check was performed, go to next step. If power seats system check was not performed, go to SYSTEM CHECKS under TROUBLE SHOOTING in POWER SEATS - DEVILLE & ELDORADO article.
  2. Turn ignition on. Connect scan tool to Data Link Connector (DLC). Disconnect left lumbar switch connector. Using scan tool, clear DTCs. After 30 seconds, check for DTCs. If DTC is reset, go to next step. If DTC is not reset, go to step  5 .
  3. Using DVOM, measure voltage between MSM connector C1 terminal corresponding with description of set DTC and ground. See MEMORY SEAT MODULE TERMINAL IDENTIFICATION  table. If battery voltage is indicated at any terminal, go to step  6 . If battery voltage is not indicated at any terminal, go to next step.
  4. Replace MSM. See MEMORY SEAT MODULE  under REMOVAL & INSTALLATION. After repairs, go to step  7 .
  5. Replace left seat lumbar switch. See POWER SEATS - DEVILLE & ELDORADO article. Recheck system operation. After repairs, go to step  7 .
  6. Repair short to voltage in circuit that battery voltage was measured at. See WIRING DIAGRAMS  . After repairs, go to next step.
  7. Turn ignition off. Reconnect all disconnected components and connectors. Turn ignition on and clear DTCs. If DTC is no longer present, go to power seats system check.
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