Component Inspection

Check CAN communication waveform generation
1. Ignition "OFF"
2. Connect 2 channel scope to DLC terminal 3 (CAN HIGH) and 11 (CAN LOW) respectively.
3. Ignition "ON" after connecting only PCM to CAN BUS.
4. Ignition "ON" after connecting only ABS or ESP module to CAN BUS
  
  Fig 1: Identifying Signal Waveform
  
  Specification: At Ignition "ON", the waveform same as "Signal Waveform & Data" of above signal waveform.
  
  Different from "Signal Waveform & Data", if 1) both CAN HIGH and LOW signal are fixed at 2.5 V or 2) HIGH and LOW signal are fixed at 3.5 V and 1.5 V, respectively, it is due to communication error between modules.
5. Does correct waveform generate from each module?
  YES
  - Go to "VERIFICATION OF VEHICLE REPAIR ".
  NO
  - Replace the module which generates poor communication waveform, and go to "VERIFICATION OF VEHICLE REPAIR ".