PRE-RELEASE
Bus messages, ACC
| Bus messages, ACC |
For a detailed description of the car's bus system, see bus and diagnostics communication, detailed description .
ACC uses the following information
| Bus messages | Value/Unit | Transmitter | Description |
| Parking heater active | On/Off | AHM | When the heater is activated via the ICM with the ignition off, the ACC will begin to adjust the car climate |
| Auxiliary heater, coolant temperature | °C | AHM | The ACC selects the highest coolant temperature value from the ECM and AHM. Fan current and air distribution are adjusted as a function of the value |
| Steering wheel side | Right/Left | BCM | ACC controls air distribution as a function of the driver's side temperature adjustment. The passenger cannot select Hi or Lo if the driver has not done so |
| Key position, ignition switch | Lock Off On Start | CIM | ACC activated via bus |
| Windscreen washer, lever active | On/Off | CIM | The message allows automatic recirculation selection for a 30s duration after washer activation. The purpose of the function is to reduce odour emanating from washer fluid additives |
| VIN | Number 10-17 | CIM | DTC generated if ACC has a different VIN than the CIM. |
| Car speed | km/h | ECM | Speed value is used for the recirculation function and calculation model for the cabin temperature |
| Coolant temperature | °C | ECM | The value is used for cold start identification. Air distribution and fan speed are set as a function of the temperature. |
| Engine running | Not running, Idle speed, no idle | ECM | The information is used to reduce the electrical load when the engine is stationary |
| Engine speed | rpm | ECM | The value is used as a safety backup if the "Engine running" information is incorrect |
| Personal ACC settings | Auto Econ Off | ICM | ACC selects the setting depending on the personal settings made via SID and SIDC |
| Electrically heated rear window, personal settings | Auto Manual | ICM | ACC selects the setting depending on the personal settings made via SID and SIDC |
| Instrument lighting, display value | % | ICM | Display background lighting is controlled with this value |
| Instrument lighting, Night panel active | On/Off | ICM | If Night Panel is active, the display is extinguished and the control lighting is dimmed |
| Instrument illumination, rheostat value | % | ICM | The value controls control panel lighting |
| Cabin temperature, personal settings | One-zone Two-zone | ICM | ACC selects the setting depending on the personal settings made via SID and SIDC |
| Air distribution, personal settings | Defroster Panel Floor Defog Panel/Floor Tri-Level Panel/Floor/Defroster | ICM | ACC selects the setting depending on the personal settings made via SID and SIDC |
| Personal fan speed settings | Higher Nominal Lower | ICM | ACC selects the setting depending on the personal settings made via SID and SIDC |
| Recirculation, personal settings | On/Off | ICM | ACC selects the setting depending on the personal settings made via SID and SIDC |
| Seat heating, personal settings | Auto/Manual | ICM | ACC selects the setting depending on the personal settings made via SID and SIDC |
| Temperature unit | C/F | ICM | The value determines the display temperature unit |
| Electrically heated rear window | On/Off | REC | The REC activates the electrically-heated rear window when ACC sends "On" |
| Wheel speed, front left | rpm | TCS/ESP | The value is used as a safety backup if the "Car speed" information is incorrect |
| Soft top status | Closed Upper sequence Lower sequence Open | STC | ACC uses the bus message to determine when ACC status must be changed. At opening this takes place when the value moves from "Closed" to "Upper sequence". At closing this takes place when the value moves from "Open" to "Lower sequence", i.e. when the soft top cover starts the closing operation. When the soft top is raised the system returns to AUTO mode and previously set temperature. When the soft top is folded down the system moves to manual temperature setting. |
