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Body Control Module Diagnostic System Check

NOTE: Use adapter from Terminal Test Adapter Kit (J-35616-A) connected to DVOM when making all measurements.
  1. Connect scan tool to DLC. Turn ignition on. Attempt to establish communications with Platform Zone Module (PZM). If scan tool communicates with vehicle, go to next step. If scan tool does not communicate with vehicle, go to step  3 .
  2. Select DISPLAY PZM DTC function on scan tool. If any DTCs are set, go to appropriate diagnosis and repair procedure. If no DTCs are set, system is okay at this time.
  3. Attempt to establish communications with other systems on the class 2 data line. If scan tool communicates with other systems, go to next step. If scan tool does not communicate with other systems along the class 2 data line, go to DATA LINK COMMUNICATIONS DIAGNOSTIC SYSTEM CHECK  .
  4. Turn ignition off. Disconnect PZM connectors C-1 and C-2. Turn ignition on. Use DVOM to measure voltage between ground and PZM power circuits. See WIRING DIAGRAMS  . If reading is 10-15 volts, go to next step. If reading is not 10-15 volts, go to step  7 .
  5. Use DVOM to measure voltage between battery voltage and PZM ground circuits. If reading is 10-15 volts, go to next step. If reading is not 10-15 volts, go to step  8 .
  6. Replace PZM. See PLATFORM ZONE MODULE (PZM)  . After replacement, go to step  9 .
  7. Repair open or short to ground in PZM power circuit. After repairs, go to step  9 .
  8. Repair open in PZM ground circuit. After repairs, go to step  9 .
  9. Turn ignition off. Reconnect all disconnected components and connectors. Use DVOM to clear all DTCs. If DTCs do not reset, system is okay at this time. If DTCs reset, go to step  2 .
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