5 HTR4 - U6 true 5 1 Ti-Source TANK heater1 Control 5 2 Ti-Source TANK heater2 Control 5 3 Ti-Source TANK heater3 Control 5 4 Ti-Source AV&MFC Control 5 5 Spare UnUsed 5 6 Spare UnUsed 5 7 Spare UnUsed 5 8 Spare UnUsed 5 9 Spare UnUsed 5 10 Spare UnUsed 5 11 Spare UnUsed 5 12 Spare UnUsed 5 13 Spare UnUsed 5 14 Spare UnUsed 5 15 Spare UnUsed 5 16 Spare UnUsed