Bus messages
| Bus messages |
By serial is meant that the information is sent in express packages” one after the other in very fast succession.
The buses consist of a P-bus (Power-train Bus) and an I-bus (Instrument Bus). Both buses are connected to the MIU (Main Instrument Unit). The buses are electrically isolated from each other.
The diagnostic tool is not connected directly to the bus but communicates via DICE, one of the control modules connected to the I-bus, and has therefore access to all the control modules connected to the bus.
The data transfer rate on the P-bus is ten times higher than the I-bus. The reason for this is that the power-train systems cannot work properly unless information is transferred with the minimum possible delay.
All the information sent from one control module is accessible to all other control modules connected to the bus. The MIU is responsible for ensuring that information available on one bus is also available on the other bus.
The control modules send out information on the bus at regular intervals. The time between two transmissions depends on the information being sent and varies between 10 milliseconds (0.010 seconds) and 1 second. Information is also sent out by the control modules whenever the information changes.
Information is transferred between the control modules via two leads, BUS+ (green lead) and BUS- (white lead). The two leads are twisted together to reduce their sensitivity to electrical interference.
DICE
| DICE transmits | Values | Used by | The value depends on the following sensor input, signal or function |
|
Position lights
|
ON/OFF
|
SID
|
Activation by control module of relay output for main lighting relay
|
|
Rear fog light broken
|
YES/NO
|
SID
|
Control module current measurement of output to lamp
|
|
LH direction indicators
|
ON/OFF
|
MIU, SID
|
Control module activation of output to lamps
|
|
RH direction indicators
|
ON/OFF
|
MIU, SID
|
Control module activation of output to lamps
|
|
Rear fog light
|
ON/OFF
|
MIU
|
Activation by control module of output to fog lights
|
|
Acoustic signal
|
Remind
|
SID
|
Control module programming and seat-belt buckle switches, driver's door or passenger's door open (bus from TWICE)
|
|
Ignition +B
|
ON/OFF
|
TWICE, Audio system
|
Ignition switch
|
|
Ignition +15
|
ON/OFF
|
--
|
Ignition switch
|
|
Ignition +54
|
ON/OFF
|
TWICE
|
Ignition switch
|
TWICE
| TWICE transmits | Values | Used by | The value depends on the following sensor input, signal or function |
|
LH rear light broken
|
YES/NO
|
SID
|
Control module current measurement of output to lamps
|
|
RH rear light broken
|
YES/NO
|
SID
|
Control module current measurement of output to lamps
|
|
LH rear light
|
ON/OFF
|
DICE
|
Control module input supplied with current from light switch
|
|
RH rear light
|
ON/OFF
|
DICE
|
Control module input supplied with current from light switch
|
|
LH brake light broken
|
YES/NO
|
SID
|
Control module current measurement of output to lamp
|
|
RH brake light broken
|
YES/NO
|
SID
|
Control module current measurement of output to lamp
|
|
High-level brake light broken
|
YES/NO
|
SID
|
Control module current measurement of output to lamp
|
|
Brake lights
|
ON/OFF
|
SID
|
Brake light switch
|
|
Acoustic signal
|
Sound information
|
SID
|
In connection with text message
|
|
Driver's door
|
OPEN/CLOSED
|
MIU,PSM
DICE |
Door switch
|
|
Passenger door
|
OPEN/CLOSED
|
MIU,PSM
DICE |
Door switch
|
|
LH rear door
|
OPEN/CLOSED
|
MIU, DICE
|
Door switch
|
|
RH rear door
|
OPEN/CLOSED
|
MIU, DICE
|
Door switch
|
|
Boot lid
|
OPEN/CLOSED
|
MIU, DICE
|
Lid switch
|
|
Diagnostics communication
|
--
|
DICE/diagnostic tool
|
Control module should be live and the bus leads intact
|
SID
| SID transmits | Values | Used by | The value depends on the following sensor input, signal or function |
|
Rheostat level
|
0 -100 %
|
Audio, ACC, DICE, MIU
|
Rheostat control module input
|
|
Rheostat Night Panel
|
0 -100 %
|
Audio, ACC, DICE, MIU
|
Rheostat control module input reduced internally by a fixed value
|
|
Night Panel
|
ON/OFF
|
Audio, ACC, DICE, MIU
|
Button
|
|
Diagnostics communication
|
--
|
DICE/diagnostic tool
|
Control module should be live and the bus leads intact
|
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