Content .. 95 96 97 98 ..

DAF XF105. Manual - part 97

200528

3-7

Control functions

DMCI ENGINE MANAGEMENT SYSTEM

XF105 series

3.4 IMMOBILISER AND START INTERRUPTION

The complete control consists of three functions:

Fuel release immobiliser

Starter motor block immobiliser

Starter motor block if engine is running

Immobiliser

The task of the engine management system in

the immobiliser system is to release and block the

fuel supply and to block the starter motor. The

purpose of the immobiliser is to ensure that the

engine can only be started with the correct

ignition key.

When the vehicle ignition is turned on, the

immobiliser electronic unit reads the immocode

from the ignition key and compares this to the

codes (up to 5) stored in its memory. If the code

is correct, the immobiliser electronic unit creates

a coded CAN message and sends this via

V-CAN1 to the DMCI electronic unit (D965). The

DMCI electronic unit decrypts this CAN message

using the stored vehicle code. If the vehicle code

from the DMCI electronic unit and the vehicle

code from the immobiliser electronic unit are

identical, the CAN message is "approved".

The DMCI electronic unit releases the fuel supply

by on-going control of the pump units and

injectors.

If the codes do not match or there is a fault on the

CAN connection, the DMCI electronic unit will

block release of the fuel supply. The pump units

and injectors will then no longer be activated. The

DMCI electronic unit then informs the immobiliser

unit that the code was not correct and a fault code

is stored in the DMCI electronic unit and the

immobiliser electronic unit.

On the second attempt to start the DMCI will not

earth the starter motor (B010) via B09. The

starter motor will therefore not work.

If release of the fuel supply is blocked, a red fault

message is activated on the DIP master display,

the "STOP" lamp lights up and an acoustic signal

sounds. This message is sent via a CAN

message and output B22 to VIC-2.

i400993

1 2

high-side

low-side

Cyl.6

B136

1 2

high-side

low-side

Cyl.5

B135

1 2

high-side

low-side

Cyl.4

B134

1 2

high-side

low-side

Cyl.3

B133

1 2

high-side

low-side

Cyl.2

B132

A12

A23

A24

A15

A19

A16

A11

A20

1 2

high-side

low-side

Cyl.1

Pump units

B131

1 2

high-side

low-side

Cyl.6

B426

1 2

high-side

low-side

Cyl.5

B425

1 2

high-side

low-side

Cyl.4

B424

1 2

high-side

low-side

Cyl.3

B423

1 2

high-side

low-side

Cyl.2

B422

1 2

high-side

low-side

Cyl.1

Injectors

B421

A22

A21

A14

A18

A13

A10

A17

Vehicle

CAN1

low

Vehicle
CAN1
high

CAN1 low

CAN1 high

B35

B27

B09

flywheel housing

ground

Starter
motor

To battery +

To start
connector

B010

50a

50 30

B22

C20

D310

engine

warning

RED

VIC-2

shield

2 1

signal

return

F552

speed

crankshaft

A49

A50

A60

DMCI ENGINE MANAGEMENT SYSTEM

3-8

200528

Control functions

XF105 series

Note:

Fuel is released as soon as an attempt is made to

start the engine to promote a quick start. Release

of the fuel supply will only be blocked if it

becomes apparent that the codes do not match.

So the engine may already be running before it is

established that the codes do not match.

Starter motor lock

If the engine is running and the electronic unit

DMCI receives an engine speed signal then

DMCI will ensure that the starter motor can not be

activated.

Relevant components
-

Pump units (B131 to B136)

Injectors (B421 to B426)

Starter motor (B010)

Immobiliser (D912 via V-CAN1)

200528

3-9

Control functions

DMCI ENGINE MANAGEMENT SYSTEM

XF105 series

3.5 CYLINDER DETECTION AND SYNCHRONISATION

General
The electronic unit needs to know which cylinders

are doing what and when in order to calculate the

correct injection timing and the correct quantity of

fuel to be injected for each cylinder. There are 3

segments on the flywheel, which each have 18

holes and an area with two holes missing. Each

area with 2 holes missing indicates two cylinders

that are at top dead centre at the same time (1/6,

2/5 and 3/4). From the centre of the area where

two holes are missing to the actual top dead

centre of the cylinder, angle

β (81 crankshaft =

40.5

 camshaft) is covered. 13 pulses (72

crankshaft) are emitted from the centre of hole 1

to the centre of hole 13.

The camshaft has a pulse wheel with 6 teeth for

cylinder detection and an additional tooth (S) for

synchronisation. These 6 teeth for cylinder

detection are spaced at 60

 intervals. The angle

γ (15) between the synchronisation tooth and the

cylinder -1 tooth on the camshaft pulse wheel

correspond to angle

γ (30) between the 14

and

hole and the centre of the area where two

holes are missing on the crankshaft.

α = 72 crankshaft (crankshaft sensor 1

pulse)

β = 81 crankshaft = 40.5 camshaft (camshaft

sensor on cylinder -1 pulse)

γ = 30 crankshaft = 15 camshaft (camshaft

sensor on synchronisation pulse, crankshaft

signal between 14

and 15

pulse of the

previous segment)

i400996

D965

1 2

high-side

low-side

Cyl.6

B136

1 2

high-side

low-side

Cyl.5

B135

1 2

high-side

low-side

Cyl.4

B134

1 2

high-side

low-side

Cyl.3

B133

1 2

high-side

low-side

Cyl.2

B132

A12

A23

A24

A15

A19

A16

A11

A20

1 2

high-side

low-side

Cyl.1

Pump units

B131

1 2

high-side

low-side

Cyl.6

B426

1 2

high-side

low-side

Cyl.5

B425

1 2

high-side

low-side

Cyl.4

B424

1 2

high-side

low-side

Cyl.3

B423

1 2

high-side

low-side

Cyl.2

B422

1 2

high-side

low-side

Cyl.1

Injectors

B421

shield

1 2

signal

return

shield

F558

speed

camshaft

2 1

signal

return

F552

speed

crankshaft

A22

A21

A14

A18

A13

A10

A17

A49

A50

A60

A53

A54

A61

TDC

CRANK

TDC

CAM

i4 00 707

DMCI ENGINE MANAGEMENT SYSTEM

3-10

200528

Control functions

XF105 series

Synchronisation
The synchronisation procedure starts when the

engine is being started. This procedure is a

control for the electronic unit to detect the

cylinders.

The procedure starts when the electronic unit

detects a "hole" in the pulse train of the

crankshaft sensor signal (F552). At that moment

the electronic unit starts to count the crankshaft

pulses and after the 14

and 15

pulse it

immediately checks the camshaft signal (F558). If

no camshaft signal is sent, the counting

procedure is restarted after a "hole" in the

crankshaft signal.

CRANK

CAM

i4 00708

Content .. 95 96 97 98 ..