As seen from top. Pin 1 is marked with a square.
| Pin | U_On [V] | U_Off [V] | Comment |
| 1 | 18.5 | 18.5 | Connected to the AC adaptor and the battery |
| 2 | 0.0 | 0.0 | Ground |
| 3 | -0.5 | -0.5 | Battery temperature sensor? |
| 4 | 5.0 | 5.0 | ? |
| 5 | 5.0 | 5.0 | ? |
| 6 | 5.0 | 0.0 | ? |
| 7 | 5.0 | 0.0 | ? |
| 8 | 4.5 | 4.5 | ? |
| 9 | 5.0 | 0.7 | CMOS battery? |
| 10 | 0.0 | 0.0 | ? |
| 11 | 18.5 | 18.5 | Connected to the AC adaptor and the battery |
| 12 | 0.0 | 0.0 | Ground |
| 13 | -0.5 | -0.5 | Battery temperature sensor? |
| 14 | -33.0 | ? | Looks like a capacitor that is slowly discharging after switch off. No idea what this voltage is used for. |
| 15 | 0.0 | 0.0 | ? |
| 16 | 0.0 | 0.0 | ? |
| 17 | 5.0 | 0.0 | ? |
| 18 | Signal | Signal | Looks like a constantly changing signal, even with the computer switched off. |
| 19 | 0.0 | 0.0 | ? |
| 20 | 5.0 | 0.0 | ? |
As seen from top from left to right.