Signal Circuit Inspection

Check for open or short in harness
1. Ignition "ON" & engine "OFF".
2. Measure waveform between terminal "C1" of BCM ECU and chassis ground.
  Specification: Signal waveform of LIN Line communication
  
  Fig 1: Measuring Waveform Between Terminal C1 Of BCM ECU And Chassis Ground
  Courtesy of HYUNDAI MOTOR CO.
3. Is the measured waveform within specifications?
  * The existence of LIN communication waveform itself shows there's no trouble in LIN communication circuit. If there's any open or short circuit in harness, no signal is detected.
  
  YES
  - Go to "POWER CIRCUIT INSPECTION " procedure.
  NO
  - Check for open or short in signal harness. Repair as necessary and go to "VERIFICATION OF VEHICLE REPAIR " procedure.