Many malfunctions in the electrical system are caused by poor harness(es) and terminals. Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.

Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.

Has a problem been found?

	▶ Repair as necessary, go to "Verification of Vehicle Repair" procedure.
	▶ Go to "Signal Circuit Inspection" as below.

IG key "ON", Engine "OFF".

Perform "Oscilloscope" procedure in the "Vehicle S/W Management" with GDS.

Measure the signal waveform between CAN High terminal of "SMART JUNCTION BOX" harness connector and chassis ground.

Measure the signal waveform between CAN LOW terminal of "SMART JUNCTION BOX" harness connector and chassis ground.

Does the measured signal waveform follow the reference data?

	▶ Disconnect CAN communication units one by one and monitor DTC to find the cause. ▶ If the DTC erase, substitute with a known-good unit and check for proper operation. If the problem is corrected, replace the unit and go to "Verification of Vehicle Repair" procedure.
	▶ Check short to battery/ground. Repair as necessary, Go to "Verification of Vehicle Repair" procedure.