Step 1: Make sure disconnect Mac battery and charger FIRST before attached tool on the logic board, it will damaged the logic board if user does not do that.

Step 2: Make sure use DURACELL Battery for on the tool, either 4 x AA size battery or 9V battery, some time with experienced technician can use external power supply with current limit at 3.3V/1A on P1 tool, and 9V on A1534 tool or P2 tool.

Model A1278