Ignition "OFF".
Remove the main relay.
Apply 12V and a ground to 2 and 4 terminals of the main relay.
Check if the main relay works well when it is energized. (If the main relay works normally, a clicking sound can be heard.)
Does the main relay operate normally?
YES
▶ Go to next step as below.
NO
▶ Replace as necessary and go to "Verification of Vehicle Repair" procedure.