Normally the control panel sends the message to the igniter such as a gas stove or waterheater. (power).Test 1st power from control panel as you have seem to have checked, then wire power at end of wires to igniter & properly conected. All test seems fine but as you see use apperance on the igniter it would seem that someone has returned a deteective part. Do you hear it click on to get burn cycle? If not probably bad ignitor or poor ground. These people should remove themself's from the appliance industry. Best bet. listen for the click of ignitor fire first. It should rather loud. Eventhough black tip tells me possible poor resistance within unit. Probably will have to replace unit & bite the bullet. When you bring it back they won't take it. Good Luck.