WHEN REPROGRAMMING A CONTROL MODULE, ALWAYS USE THE GR-8 BATTERY MANAGEMENT SYSTEM POWER SUPPLY MODE. IF NOT USED, THE CONTROL MODULE REPROGRAMMING MAY FAIL DUE TO A WEAK VEHICLE BATTERY.THE GR-8 BATTERY MANAGEMENT SYSTEM POWER SUPPLY MODE PREVENTS THE VEHICLE BATTERY FROM BEING DISCHARGED. THIS ALLOWS THE IDS TO REPROGRAM A CONTROL MODULE WITHOUT INTERFERENCE FROM A WEAK OR UNDERCHARGED VEHICLE BATTERY. NOTE: CONTROL MODULE DAMAGE MAY OCCUR IF THE GR-8 BATTERY MANAGEMENT SYSTEM POWER SUPPLY MODE IS NOT USED.