Diagnostic Mode
5-baud setup, test commands, data packet format, and voltage byte table for the Lucas 5AS.
Setup: 5-baud init with address 0x1C (replies 0x55 0x83 0x76).
Test commands
Each device has an on and an off command. The low nibble selects the device, the high nibble the action (3 = on, 2 = off): on = 0x30 | device, off = 0x20 | device.
| Device | On | Off | Pin | Active |
|---|---|---|---|---|
| CDL Unlock Motor | 0x31 | 0x21 | J1-11 | HIGH |
| 3TH Output | 0x32 | 0x22 | J1-12 | LOW |
| CDL Lock Motor | 0x33 | 0x23 | J1-13 | HIGH |
| Chime | 0x34 | 0x24 | J1-25 | LOW |
| Volumetric Sensor Power | 0x35 | 0x25 | J1-14 | HIGH |
| ? | 0x36 | 0x26 | ? | ? |
| Superlock Motors | 0x37 | 0x27 | J2-01 | HIGH |
| Horn Relay | 0x38 | 0x28 | J1-08 | LOW |
| LED | 0x39 | 0x29 | J1-17 | LOW |
| Crank Relay | 0x3A | 0x2A | J1-23 | LOW |
| MEMS ECU Link | 0x3B | 0x2B | J1-09 | LOW |
| ? | 0x3C | 0x2C | ? | ? |
| Hazard Flash (L/R) | 0x3D | 0x2D | J2-06/07 | HIGH |
| Energiser Coil Signal | 0x3E | 0x2E | J2-11 | HIGH |
| Volumetric Program | 0x3F | 0x2F | J2-08 | LOW |
Other commands
| Command | Value |
|---|---|
| Keep alive | 0xF0 (assumption) |
| Disconnect | 0xF6 |
| Start key programming | 0x5F |
| End key programming | 0x6F |
| Request data packet | 0x83 |
Key programming erases all stored keys. Press each fob's lock button ≥8 times until the horn sounds; up to 4 keys. Test the horn first with the actuator tests.
Diagnostic packet (in progress — likely more fields)
Returned in response to 0x83. Indices not listed are unknown or unused.
| Index | Field | How | Pin |
|---|---|---|---|
| 0 | Packet size | — | — |
| 1 | Bonnet | bit 7 (0 / 0x80) | J1-18 |
| 2 | Driver's Sill Up | bit 7 (0 / 0x80) | J1-04 |
| 3 | Driver's Sill Down | bit 7 (0 / 0x80) | J1-19 |
| 4 | Passenger's Sill Up | bit 7 (0 / 0x80) | J1-05 |
| 6 | Ignition | bit 7 (0 / 0x80) | J1-01 |
| 7 | Key Barrel Switch | bit 7 (0 / 0x80) | J1-22 |
| 9 | Driver's Door Open | bit 7 (0 / 0x80) | J1-07 |
| 11 | Boot Open | bit 7 (0 / 0x80) | J1-21 |
| 12 | Inertia Switch | bit 7 (0 / 0x80) | J2-09 |
| 13 | Passenger Door Open | bit 7 (0 / 0x80) | J1-06 |
| 14 | Input bitfield 1 | packed, see below | — |
| 15 | Input bitfield 2 | packed, see below | — |
| 16–19 | Key Counter 1–4 | — | — |
| 20–22 | Serial Number Byte 0–2 | decimal, 3-byte LSB first | — |
| 24–25 | EKA Code Byte 0–1 | BCD, 2 digits per byte | — |
| 30 | Voltage | non-linear (see below) | — |
| 36 on | Unit Description | e.g. P2.005AS-98MY | — |
Indices 14 and 15 pack the input states as individual bits (0 = inactive, 1 = active). These are the same states exposed at bit 7 of indices 1–13.
Index 14 (0x0E)
| Bit | Signal | Pin |
|---|---|---|
| 0 | Ignition | J1-01 |
| 1 | Key Barrel Switch | J1-22 |
| 2 | — | — |
| 3 | Driver's Door Open | J1-07 |
| 4 | — | — |
| 5 | Boot Open | J1-21 |
| 6 | Inertia Switch | J2-09 |
| 7 | Passenger Door Open | J1-06 |
Index 15 (0x0F)
| Bit | Signal | Pin |
|---|---|---|
| 0 | Bonnet | J1-18 |
| 1 | Driver's Sill Up | J1-04 |
| 2 | — | — |
| 3 | Driver's Sill Down | J1-19 |
| 4 | — | — |
| 5 | Passenger's Sill Up | J1-05 |
| 6 | — | — |
| 7 | Volumetric Sensor Signal | J1-20 |
Voltage byte
| Voltage | Binary | Decimal | Δ |
|---|---|---|---|
| 10.5 V | 11011110 | 222 | — |
| 11.0 V | 11100101 | 229 | 7 |
| 11.5 V | 11101010 | 234 | 5 |
| 12.0 V | 11101110 | 238 | 4 |
| 12.5 V | 11110001 | 241 | 3 |
| 13.0 V | 11110100 | 244 | 3 |
| 13.5 V | 11110110 | 246 | 2 |
| 14.0 V | 11111000 | 248 | 2 |