| Message ID | Bit | Function |
| Priority | 3 bits | Defines message priority during arbitration |
| Reserved | 1 bit | This bit is reserved for future, always it must be set as zero |
| Data page | 1 bit | expansion of possible parameter group |
| PDU format (PF) | 8 bits | PF indicate message transmitted with a destination address or always broadcast message |
| PDU specific (PS) | 8 bits | If PF is between 0 and 239 then PS contains addressable MSG PDU1 If PF is between 240 and 255 then PS contains only broadcast MSG PDU2 |
| Source Address | 8 bits | Source Address |
| SAE J1939 | Total 29 Bits | |