WMM Control Unit Signal Circuit Inspection

Check LIN communication circuit
1. Ignition "ON" and Engine "OFF"
2. Connect scantool and select VEHICLE SCOPEMETER function.
3. Measure waveform between "LIN communication" of WMM connector and chassis ground.
  Specification : If LIN communication waveform is displayed, it is OK.
4. Is LIN communication waveform displayed within specification?
  YES:
  - Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration or damage.
  Repair or replace as necessary and then go to "VERIFICATION OF VEHICLE REPAIR " procedure.
  
  NO:
  - Check the LIN communication harness of the WMM for an open and short.
  Repair as necessary and then go to "VERIFICATION OF VEHICLE REPAIR " procedure.