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On-board computers and the CAN line
The following on-board computers make up the electrical system of the Multistrada 1200 and are connected with each other via the CAN line (or network):
 
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The drawing illustrates the network connecting the different computers ('nodes') on the Multistrada 1200. The DTC system is not a separate unit and is integrated in the BBS, whereas the ABS unit is not connected to the network directly.
 
The main characteristics of the computers used on the Multistrada 1200 are described as follows:
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The Dash Board unit does not only display specific information of use to the rider, but is also connected to the sensors and actuators installed on the motorcycle. The unit makes the information received from the sensors available over the network and controls the actuators, also in response to orders received from other computers connected to the network. The unit's service display also visualises any vehicle electronic system faults
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The Hands Free unit allows the rider to start the engine without inserting a conventional key into the ignition switch. This makes starting the motorcycle easier and quicker. The system also offers increased theft protection
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The ECU manages the functions of the engine and also controls the ride by wire system. The ride by wire system modulates throttle valve aperture via an electric actuator coordinated by the ECU. The ECU receives a “torque demand” signal from a po­tentiometer linked to the throttle grip. Three different throttle valve aperture regimens are stored in the ECU, which make dif­ferent maximum power values and different torque curves possible.
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The Electronic Suspension unit adjusts the suspension set-up with electric actuators, rendering the use of conventional adjust­ment devices unnecessary. This is a passive adjustment system, meaning that it does not adapt automatically while the vehicle is in use
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Like the Dash Board unit, the BBS is connected to sensors and actuators installed on the vehicle. The unit makes the information received from the sensors available over the network and controls the actuators, also in response to orders received from other computers connected to the network. It also has another fundamental function, as it gathers all the errors registered by the other computers due to specific faults. The software in the BBS also performs the DTC function, which regulates engine torque delivery to prevent wheelspin under acceleration. When replacing the BBS, if the motorcycle is equipped with electronic sus­pension or heated handgrips, the BBS must be correctly initialised with the DDS.
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This diagram shows the main inputs and outputs of the BBS and Dash Board units.
 
The networked connection of the individual computers (nodes) creates a distributed system in which the nodes may communi­cate with one another and coordinate their actions by exchanging messages. This offers the following advantages:
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A distributed system needs less sensors, substantially simplifying the electrical system, as information provided by certain sen­sors may be shared, rendering it unnecessary to provide duplicate sensors for each node.
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The network allowing communication between the different nodes on the Multistrada 1200 is a serial (bus) type CAN (Controller Area Network) network. Each node contains a circuit that can transmit and receive data to and from the network in accordance with priorities defined by specific bits (electrical impulses) included within the data itself (the message travelling over the network is always the one with the highest priority). As a result, the CAN bus network does not need to be managed with a specific cen­tralised arbitration procedure that defines the priorities with which the elements connected to the network must communicate. Each message travelling over the CAN network consists of a “train” of electrical impulses containing, as mentioned previously, the priority - in other terms the type of message - the data itself, the confirmation of reception and other data necessary for correct transmission and reception. The train of impulses is transmitted to the bus, which consists of two wires - CAN H and CAN L. Each node extrapolates the message and, as a result, the data contained, processing the sequences of impulses received from on the CAN H and CAN L wires independently. This ensures superior reliability, as any interference in the electrical signals is effectively subtracted and eliminated.
One drawing shows the typical voltages on the CAN H and CAN L wires for each electrical impulse contained in the train “trans­porting” information shared by the nodes connected to the network. The other drawing shows the signal extrapolated by each node from the difference between the two former signals.
 
In short, the advantages of using the CAN bus are as follows:
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Note that the control function for the electrical impulses travelling over the CAN network has no validity for diagnostic purposes, as the information contained in the trains themselves cannot be identified.
Fault indication
The DDS (Diagnosis Ducati System) indicates all active errors and all inactive but stored errors gathered by the BBS. A simplified summary of the active errors is also shown in the dashboard service display when the dashboard is switched on. Simultaneously, the EOBD warning light is also activated, independently of the types of the errors themselves. In the event of more than one active error, the errors are shown cyclically on the service display for 3 seconds each.
 
In the event of a CAN line fault (CAN OFF), the dashboard cannot transmit data and the electrical system behaves as follows:
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If the CAN line fault is no longer present (fault resolved), normal operation is resumed and the CAN error disappears from the service display.
 
Other faults relative to the CAN line and indicated on the dashboard by the service display and by activation of the EOBD warning light, are described as follows:
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DEVICE ECU the ECU node (engine control unit) is not recognised by the network or is not communicating with the network. In this case, the DDS may display the following messages relative to ECU function diagnosis: ECU counter, ECU no frame, ECU not compatible
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DEVICE Dashboard the Dash Board node is not recognised by the network or is not communicating with the network. In this case, the DDS may display the following messages relative to Dashboard function diagnosis: Dashboard counter, Dashboard no frame, Dashboard not compatible
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DEVICE Hands free the Hands Free node (facilitated keyless start system) is not recognised by the network or is not com­municating with the network. In this case, the DDS may display the following messages relative to Hands Free function diag­nosis: Hands free counter, Hands free no frame, Hands free not compatible
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DEVICE DES the Electronic Suspension node (suspension with passive electronic adjustment) is not recognised by the network or is not communicating with the network. In this case, the DDS may display the following messages relative to Suspension function diagnosis: Suspension counter, Suspension no frame, Suspension not compatible
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BBS/DTC DEVICE this message is transmitted by the engine control unit to the dashboard and indicates that the BBS is not recognised by the network or is not communicating with the network. In this case, the DDS may display the following messages relative to BBS/DTC function diagnosis: BBS/DTC counter, BBS/DTC no frame
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Device SW compatibility error- UNKNOWN DEVICE the BBS does not recognise the network to which it is connected
Dashboard warning and indicator light key (some of these are used to indicate faults in the electric - electronic system):
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Warning
when diagnosing one of more elements in the electric – electronic system, also check that there are no error codes indicating CAN line faults. If any error codes relative to CAN line faults are noted, the relative fault must always be resolved as it may be correlated with other specific faults.
Operating principle of DTC
The DTC function integrated in the BBS controls engine torque delivery to prevent loss of rear wheel grip. The BBS receives the angular speed signals relative to the front and rear wheels. In relation to the wheel diameter and tyre cross section, these signals is converted into the tangential speed values for the front and rear wheels. The vehicle speed is ascertained from these values and transmitted to the dashboard over the CAN network. If the tangential speed of the rear wheel exceeds the tangential speed of the front wheel by a given percentage, this indicates that the rear wheel is wheelspinning excessively. At this point the DTC intervenes, requesting the ECU to reduce engine torque. A number of other sensors are also included inside the BBS to deter­mine if the vehicle is wheeling, in which case the DTC will not intervene until a predetermined vehicle speed is reached. To en­sure that the Ducati Traction Control functions correctly, never fit tyres other than those authorised by Ducati. On the Multistrada 1200 there are 8 different DTC levels (from 1 to 8):
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The DTC may be disabled by the rider.
This qualitative graph illustrates the relationship between rear wheelspin and degree of DTC intervention (engine torque reduc­tion).
The dashboard specifically indicates if DTC is enabled or if it has been disabled by the rider.
 
In the event of internal BBS faults relative to the DTC function, the DDS shows the following messages relative to BBS/DTC diagnosis:
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Warning
Faults relative to DTC are only detected if DTC is enabled. In the event of any wheel speed sensor faults or internal BBS faults, DTC is disabled.
Riding Modes
The rider may select between four different riding modes (Sport, Touring, Urban and Enduro) from the dashboard and via the “turn indicator reset” button (3). Each riding mode contains settings for the following:
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The rider may modify the parameter settings of each riding mode or restore the default settings. The default settings are sum­marised in the following table.
 
 
The battery charging circuit and power distribution
On the Multistrada 1200, the +15V (KEY ON power) voltage does not come from a conventional ignition key, but from PIN 30 of the Hands Free relay. This relay is switched to closed state by the Hands Free unit when the latter enables power on for the ignition and engine. The Hands Free relay receives +30V voltage (battery voltage), protected by a general 30A fuse.
The “Instrument panel“ and the “BBS“ fuses protect the power supplies of the devices controlled by the two control units.
 
The three phase alternator has three windings (l1, l2, l3), connected to one another in a “triangle” or “delta” configuration. The electrical terminals R, S and T are connected to the voltage regulator.
The drawing illustrates the “triangle” or “delta” configuration connection of the three windings of the three phase alternator.
 
The alternator has the following characteristics:
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The sinusoid voltage generated by each phase during each rotation of the rotor is at a higher frequency than with the unit in­stalled on SBK models. This is why the alternator used on the Multistrada 1200 is known as a high-frequency unit. This charac­teristic make the following possible:
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The curve (A) represents the current generated by the alternator used on SBK models in relation to engine speed. The curve (B) indicates the current generated by the alternator used on the Multistrada 1200, also in relation to engine speed. It can be seen that the red curve indicates a higher current intensity at low engine speeds and a lower current intensity at higher engine speeds.
 
The voltage regulator is constructed with specific electronic circuits (using MOSFET instead of SCR diodes) which limit operating temperature and, as a result, improve reliability. The regulator can withstand a maximum current of 50A (maximum current for the regulator used on SBK models is 35A) and has integrated waterproof electrical connections.
 
In the event of incorrect battery voltage (too low or too high), the message “Battery” is shown in the service display. The DDS also indicates if an excessively low or high battery voltage is detected (Battery voltage diagnosis: High voltage, Low voltage).
 
In the event of a battery charging circuit fault, check the following in the order given:
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Check the integrity of the electrical circuit connecting the alternator to the regulator and the regulator to the battery (to carry out these tests, disconnect the battery cables and check the state of the electrical connections and cables and check for short cir­cuits). Also check the ground connection of the circuit on the engine
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At an engine speed of 2,500 rpm, the alternating charging voltage measured between T – R, T – S and R – S with the alternator disconnected from the voltage regulator (“zero load”) must be between 40V and 50V. This measurement must only be made with a cold engine, and the alternator must only be disconnected from the voltage regulator in KEY OFF state. Replace the al­ternator if the voltage measured is incorrect.
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Check the insulation relative to ground of each of the three terminals (the resistance between R - Ground, T - Ground and S - Ground must be infinite). If insulation is compromised, change the alternator windings
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The battery state of charge must be checked first before checking the function of the voltage regulator. Battery state of charge is ideal if the voltage measured between the battery poles is between 12.2V and 12.7V. The battery must be disconnected from the motorcycle electrical system for this measurement. After reconnecting the battery to the motorcycle electrical system, turn the engine on and maintain an engine speed of 3,000 rpm. At this engine speed, the voltage measured at the battery poles must be between 14V and 15V. If the battery voltage measured is incorrect, replace the voltage regulator
Ground connection locations
The negative cable, which is normally connected to the negative pole of the battery, is fastened to the crankcase. From here, the cable branches off and splits up within the electrical system to carry the ground connection to the different elements in the sys­tem.
This image illustrates the ground connection on the left hand side of the crankcase, near the starter motor.
 
With the battery cables disconnected, check that the resistance between an unpainted part of the frame and the end of the ground cable normally connected to the battery is zero. With the battery cables still disconnected, check that the resistance be­tween an unpainted part of the engine and the end of the ground cable normally connected to the battery is zero.
Electrical power for lighting and signalling devices
The front and rear running lights consist of LED units with light conduits. As a result, the light source is not visible as the light is diffused through the surface of the light conduit.
These two images illustrate the front and rear running lights with light conduits.
The low beam lights, shown on in the image, are externally mounted. The high beam lights are internally mounted.
Rear-view of front headlamp. The high beam light connections are at the two outer ends, the low beam connections are at the sides and the connection for the LED power module is at the centre, with the connector cable.
This image shows a top view of the headlamp. Note the running light LED power module at the centre.
To access the tail light - turn indicators unit remove the four lower screws of the number plate holder as described in Sect. 7 - 18, “Removal of the licence plate holder“. The electrical connections are located inside the small black plastic shield element, located at the left hand end of the saddle mounting frame.
 
The BBS and the Dash Board unit provide electric power to the lighting and signal devices, which therefore have no conventional power supply passing via a fuse and no electric switchgear set on the handlebar. Commands for the lights and signals are in fact sent to the control units, which then activate the relative lighting devices. The following table indicates the types of devices used, the type of power supply and whether or not the devices are testable.
 
Rear turn indicators with incandescent bulbs, commanded directly from BBS
License plate light with incandescent bulb commanded directly from Dash Board
Low beam lights with incandescent bulbs, commanded by relay activated by Dash Board
High beam lights with incandescent bulbs, commanded by relay activated by Dash Board
Front and rear LED running lights, com­manded directly from BBS
As soon as you start the engine the low beam turns on automatically. In KEY-ON condition and engine off it is possible to turn on the high and low beams that will switch off after 60 seconds if the engine is not started.
Location of elements on motorcycle
(A) Injection relay; (B) ETV relay (throttle valve operating engine); (C) Radiator fan relay; (D) engine control unit.
(A) Suspensions control unit (if supplied as outfit); (B) Vehicle electronic system diagnosis socket; (C) BBS (Black Box System or Central electronics); (D) ABS hydraulic unit with integrated control unit (if supplied as outfit); (E) Diagnosis socket for ABS system only.
Fuses located at the front left of the vehicle.
(A) 15A high beam/low beam relay; (B) 10A instrument panel (only power supplies); (C) 5A engine control unit (ECU); (D) 15A +15 - KEY ON from PIN 30 Hands free relay; (E) 20A Fuel pump/injectors relay (injection relay); (F) 10A Ride by wire ETV (throttle control electric motor).
 
Fuses located at the rear right of the vehicle.
(A) 7.5A BBS (only power supplies); (B) 7.5A Navigator system, sockets and anti-theft system; (C) 25A ABS, (D) 30A ABS; (E) 10A Radiator fans; (F) 7.5A Diagnosis.
(A) Hands free relay; (B) High beam relay; (C) Low beam relay; (D) Front fuses.
(A) Rear fuses; (B) Starter motor relay; (C) Main fuse (30A); (D) Electric pump for rear shock absorber spring preload.
The voltage regulator is mounted on the right hand side of the motorcycle, at the mounting point for the saddle mounting frame on the main frame.
 
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