[LS short box]

In a nut shell the brake light switch closes when the plunger is depressed sending 12 volts to the brake lights. The TCC needs just opposite, when the plunger is depressed the contact opens to disengage the lock up converter. So using a multi meter set to ohms when the plunger is depressed. the brake switch contacts should allow current flow when the plunger is depressed. The TCC contacts should not allow current flow when the plunger is depressed the meter showing an open contact.