| OBD-II Pin # | OBD-II Signal | DB-25F Signal | DB-25F Pin # |
|---|
| 1 | Discretionary* (GMLAN SW CAN) | SW CAN | 1 |
| 2 | SAE J1850 + | J1850 VPW | 2 |
| 3 | Discretionary* (GMLAN MS CAN H) | MS CAN H | 5 |
| 4 | Chassis Ground | N/C | N/C |
| 5 | Signal Ground | PWR GND | 13 |
| 6 | Discretionary* (GMLAN HS CAN H) | HS CAN 1 H | 14 |
| 7 | ISO9141/K | ISO9141/K/LIN1 | 8 |
| 8 | Discretionary* | N/C | N/C |
| 9 | Discretionary* (GM ALDL) | HS CAN 3 H | 19 |
| 10 | SAE J1850 – | HS CAN 3 L | 20 |
| 11 | Discretionary* (GMLAN MS CAN L) | MS CAN L | 6 |
| 12 | Discretionary* | HS CAN 2 H | 16 |
| 13 | Discretionary* | HS CAN 2 L | 17 |
| 14 | Discretionary* (GMLAN HS CAN L) | HS CAN 1 L | 15 |
| 15 | L line of ISO 9141-2 | ISO L | 7 |
| 16 | Unswitched Vehicle Battery Positive | VBATT | 25 |
