| A1 | GND | Ground for audio unit (G404) | 
| A2 | ILLUMI CANCEL | Detects function signal for illumination cancel | 
| A3 | ?B BACKUP MAIN | Continuous power source | 
| A4 | ILLUMI? | Detects illumination on signal | 
| A5 | RL SPKR? | Outputs sound signal for left rear speaker | 
| A6 | RL SPKR? | Outputs sound signal for left rear speaker | 
| A7* | GND | Detects number of speaker for self-diagnosis (connect to G403) | 
| A8 | Not used | ??? | 
| A9 | RR SPKR? | Outputs sound signal for right rear speaker | 
| A10 | RR SPKR? | Outputs sound signal for right rear speaker | 
| A11 | REMOTE SW GND | Audio remote switch ground | 
| A12 | Not used | ??? | 
| A13 | K LINE | Detects scan tool signal (serial data) | 
| A14 | Not used | ??? | 
| A15 | FL SPKR? | Outputs sound signal for left front speaker | 
| A16 | FL SPKR? | Outputs sound signal for left front speaker | 
| A17 | Not used | ??? | 
| A18 | Not used | ??? | 
| A19 | FR SPKR? | Outputs sound signal for right front speaker | 
| A20 | FR SPKR? | Outputs sound signal for right front speaker | 
| A21 | Not used | ??? | 
| A22 | AUDIO REMOTE SW | Detects control signal from audio remote switch | 
| A23 | Not used | ??? | 
| A24 | ACC | Power source for accessories |