CAN Signal Inspection

Ignition switch "OFF"
Connect VMI to GDS and launch the oscilloscope (2 Channel):
Channel A (+): Pin No. 15 (C-CAN High) terminal (IGPM connector)

Channel A (-): Ground

Channel B (+): Pin No. 16 (C-CAN Low) terminal (IGPM connector)

Channel B (-): Ground
Ignition switch "ON"
Specification: C-CAN High voltage - Approx. 2.8V/C-CAN Low voltage - Approx. 2.2V (Average)

Fig 1: Screen Display - Normal C-CAN Signal Waveform
Courtesy of KIA MOTORS AMERICA, INC.
Is the measured value within specification?
YES
- Fault might be intermittent and caused either by poor contact in connectors or wiring harness, or it has been repaired and control module memory is not cleared yet. Thoroughly check terminal of battery, all connectors (and connections) for looseness, bending, corrosion, contamination, deterioration, and/or damage.
- Repair or replace as necessary and then go to "VERIFICATION OF VEHICLE REPAIR " procedure.
NO
- Repair open or short in C-CAN communication line and then, go to "VERIFICATION OF VEHICLE REPAIR " procedure.
- If problem keep occurs, go to "COMPONENT INSPECTION " procedure.