BRAKELIGHT Switch (BTSI Solenoid)

Check brakelight switch connector for opens, spread or corroded terminals. Test switch by checking continuity across terminal "A" and terminal No. 4 of switch. See Figure. Continuity should be present with brake released. Continuity should not be present with brake applied. If damaged, replace brakelight switch.

Fig 1: Identifying BTSI Solenoid (Saturn)

Courtesy of GENERAL MOTORS CORP.