Technical Information · issue 1 of 2010
New chain saw STIHL MS 441 C-M
IssueTI 1/2010
Engine family 1138
Full text
Page 1 of 22
STIH)
Technical Information 01.2010
New chain saw STIHL MS 441 C-M – Series 1138
Contents
1. Functional description
2. Starting / stopping the engine
3. Specifications
4. Servicing accessories
5. Servicing
STIHL M-Tronic
The new STIHL MS 441 C-M chain saw expands Electronic cold / warm start detection permits a
the MS 441 series with the new, innovative M-Tronic position "Start }" on the Master Control Lever™ for
engine management system. starting the chain saw. The starting procedure is
The MS 441 C-M is the first professional STIHL simplified requiring fewer pulls of the starter rope,
chain saw equipped with the new, fully electronic without switching from "choke shutter closed" to
M-Tronic engine management system. It regulates "starting acceleration". Good acceleration is
the ignition timing and electronically adjusts the fuel realized using the electronic controller. By
flow, taking external conditions into account. monitoring the engine temperature and speed, the
control unit continually checks the operating state of
the chain saw and adjusts the fuel flow so that
optimal engine power is always available. The
electronic memory (memory function) remembers
the settings from the last time the machine was
used. Thus if the machine is restarted under the
same general conditions, the full power of the
engine is available immediately.
According to the system of product names for
convenience features (C-versions), machines with
M-Tronic are denoted with an "M".
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)m~ge 2 Technical Information 01.2010
1. Functional description
1.1 Components
4
2
5
219TI046 KN
219TI072 KN
1
Control unit (1) Solenoid valve (4)
Control center for the optimum adjustment of fuel electronically switched solenoid valve adjusts the
flow, the exact ignition timing and the memory overall fuel flow in milliseconds – this permits
function. adjustment from 0 % to 100 % fuel
Second pair of poles (2) Micro switch (5)
Supplies power to the control unit and solenoid
Identifies the position of the choke shutter – start
valve
detection
Wiring harness (3) Diagnostic jack (6)
Connects control unit, solenoid valve, micro switch
Receptacle for a software-based diagnostic unit
and diagnostic jack
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Technical Information 01.2010 Page 3
1.2 Starting 1.5 Full throttle
Set the Master Control Lever™ to } (Start) – choke A regulating sequence will be initiated only if the
shutter is closed. Simultaneously, the micro switch chain saw is operated for approx. 2 seconds under
on the switching device is closed. During starting uniform conditions, e.g., cutting to length, at a speed
and if the engine is running, the control unit is between 8,000 rpm and 11,200 rpm.
powered via the second pair of poles.
The solenoid valve closes for approx. 0.1 seconds –
The following processes occur within the space of the current fuel-air mixture is made leaner.
milliseconds.
The speed change due to the brief leaning of the mix
The microprocessor detects that the micro switch is so slight as to be imperceptible to the user.
has been actuated and thus the choke shutter is The resulting engine speed pattern is analyzed by
closed and computes the necessary amount of fuel the microprocessor.
and the ignition timing for the start.
During starting, the fuel-air mixture in the carburetor
is highly concentrated ("enriched") – a large quantity The following results are possible:
of fuel flows through the solenoid valve. After initial Engine speed increases
combustion, the quantity of fuel is reduced. The
engine does not stall out because the fuel-air . The mix was too rich before the solenoid valve
mixture is too rich; it keeps running and can be closed – the fuel flow is reduced for next phase
accelerated immediately. After the throttle trigger is of operation
actuated, the choke shutter and micro switch open Engine speed decreases
and the Master Control Lever™ jumps to the
. The mix was too lean before the solenoid valve
operating position F. The control unit receives the
closed – the fuel flow is increased for the next
information "choke shutter open" and the
phase of operation
microprocessor adjusts the amount of fuel.
Engine speed does not change
1.3 Idle . The current carburetor setting is optimal – the
The target idle speed is controlled by adjusting the current setting will be maintained
ignition timing and the fuel flow.
The engine speed can be influenced instantly by 1.6 Maximum speed
adjusting the ignition timing. Changing the fuel flow The maximum permissible speed is kept constant
only influences the engine speed after 5 to by controling the fuel-air mixture and the ignition
10 revolutions of the crankshaft. timing.
For this reasons, to establish steady idling, the
ignition timing is adjusted first and then the fuel flow.
The fuel flow control is designed so that the target
idle speed is attained with the target ignition timing.
1.4 Acceleration
If the control unit detects that the engine is being
accelerated, the ignition timing is advanced and the
fuel flow is increased – the fuel-air mixture is
enriched. Optimal, spontaneous acceleration.
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)m~ge 4 Technical Information 01.2010
1.7 Advantages 2. Starting / stopping the engine
Easy starting –
2.1 Positions of the Master Control Lever™
With M-Tronic there is only one start position on the
Master Control Lever™ because the system detects
cold or warm starts and electronically computes the
exact fuel flow allowing starting with a few pulls of STOP
the starter rope and immediate full throttle.
Constant optimum engine performance –
0
By monitoring of the engine temperature and speed,
the control unit continually checks the operating
state of the chain saw and adjusts the fuel flow for
219TI067 KN
constant optimum engine performance.
Very good acceleration –
STOP 0 Engine off – ignition is
The MS 441 C-M accelerates spontaneously and switched off
quickly by virtue of electronic ignition timing control
Operating position F Engine is running or can
and fuel flow adjustment.
start
Start } This position is for starting
No manual carburetor adjustments – the engine
M-Tronic electronically adjusts the fuel-air mixture in
the carburetor: for all operating states such as start,
idle, part throttle and full throttle as well as taking Adjusting the Master Control Lever™
into account the external conditions, e.g., use at To adjust the Master Control Lever™ from the
varying altitudes, changing temperatures or fuel operating position F to Start }, press and hold
quality (caloric value – energy content of the fuel, down the throttle trigger interlock and throttle trigger
alcohol content, knock resistance). simultaneously – set Master Control Lever™ to Start
Memory function (electronic memory) – } and simultaneously release the throttle trigger
and throttle trigger interlock.
M-Tronic remembers, for an unlimited period of
time, the settings from the last time the saw was Simultaneously pressing the throttle trigger interlock
used and retrieves them the next time the chain saw and blipping the throttle trigger causes the Master
is started. Thus full engine power is available Control Lever™ to jump from the start } position to
immediately each time the machine is started under the operating position F.
the same external conditions.
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Technical Information 01.2010 Page 5
2.2 Starting the chain saw Once the engine is running
There must not be anyone within the swivel range of
the chain saw.
Press the button on the decompression valve
1
1 2
219TI068 KN
2 . Simultaneously blip the throttle trigger interlock
4 and the throttle trigger (2); the Master Control
219TI068 KN
3 Lever™ (1) jumps to the operating position F
and the engine begins to idle
. Pull the hand guard toward the handlebar – the
. Push the hand guard (1) forward to activate the chain brake is released – the chain saw is ready
chain brake for use
. Simultaneously press and hold down the throttle
trigger interlock (2) and throttle trigger (3) – set 2.3 If the engine does not start
Master Control Lever™ (4) to Start } and The starter grip may not have been pulled briskly
simultaneously release the throttle trigger and and forcefully; the fuel-air mixture is probably too
throttle trigger interlock rich (engine is flooded).
. Hold and start the chain saw . Move the Master Control Lever™ to the
When starting the engine for the first time or after a operating position F
long period of disuse, it may be necessary to pull the . Hold and start the chain saw
starter rope several times – to prime the fuel line. In
this case, allow the engine to run for a short time in or:
the Start } position. . Remove and dry the spark plug
. Move the Master Control Lever™ to the stop
position 0
. Crank the engine several times with the starter
– to clear the combustion chamber
. Refit the spark plug
. Move the Master Control Lever™ to the
operating position F
. Hold and start the chain saw
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)m~ge 6 Technical Information 01.2010
3. Specifications 5. Servicing
Engine The specific national safety regulations and the
safety instructions in the instruction manual must be
STIHL single cylinder two- observed if the machine has to be started up during
stroke engine servicing.
Displacement: 4.31 cu.in.
70.7 cm3 5.1 Troubleshooting plan
Engine power to ISO 8893: 5.6 hp 4.2 kW The flow charts that follow deal with specific parts
at 9,500 rpm diagnosis and troubleshooting for the M-Tronic
Idle speed: 2,800 rpm engine management system.
High speed setting when 13,500 rpm The flow charts help you to take the correct step at
performing repairs (with bar the correct time.
and chain):
All other diagnosis and repair operations remain
Weight:
unchanged.
– MS 441 C-M 14.6 lbs. (6.6 kg)
4. Servicing accessories
4.1 New special tool
– Test lead M-Tronic 5910 840 0903
219TI047 KN
The M-Tronic test lead 5910 840 0903 permits
simple diagnosis.
4.2 Existing special tools
The existing special tools are listed in the Service
Manual for STIHL MS 441.
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Technical Information 01.2010 Page 7
5.1.1 Engine does not start
Engine does not start
yes
Set Master Control Lever™ to Is it possible to start the Troubleshooting completed
position } engine?
Test ignition system
no according to flow chart
"Ignition system troubleshooting“,
see Service Manual
yes
yes
Check ignition Ignition spark Is it possible to start the
(spark plug, spark plug boot, ignition present? engine?
spark)
Mechanically check start detection Mechanically Replace switching device
Micro switch, actuating lever OK? if necessary
yes
Are no
Check start detection and wiring target values attained? Replace switching device and/or
harness electrically wiring harness
(b 5.6,b 5.7)
yes
Check solenoid valve Are target values Replace carburetor
attained? (b 5.5)
yes
Look for a fault in the fuel path, check
engine for leaks
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)m~ge 8 Technical Information 01.2010
5.1.2 Engine does not start in position }
Engine does not start in position }
(Start) – engine floods. The flooded
engine can be started in position F
yes
Is it possible to start the Troubleshooting completed
engine?
Check start detection Replace switching device
(micro switch, actuating lever) no if necessary
Mechanically
clean if necessary OK?
yes
no Repair switching device and/or wiring
Check start detection and wiring Are target values attained?
harness (b 5.6,b 5.7) harness or replace if necessary
yes
Look for a fault in the fuel path
(inlet needle, lever, spring,
membrane),
check engine for leaks
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Technical Information 01.2010 Page 9
5.1.3 Engine speed drops under load –
low power
Engine speed drops under load – low
power
Check the air filter and clean or
replace if necessary
Carry out five uniform cuts to length
(speed between
8,000 rpm and 11,200 rpm
approx. 11.8 in. (30 cm) log diameter)
yes no
Chain saw
OK?
Troubleshooting completed Look for a fault in the fuel path, check
engine for leaks
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)m~ge 10 Technical Information 01.2010
5.1.4 Ignition – no ignition spark
No ignition spark
yes
Set Master Control Lever™ to Is it possible to start the Troubleshooting completed
position } engine?
Check the flywheel Establish correct control unit/flywheel
Combination
(two pairs of poles?) combination
OK?
yes
Check air gap Air gap
(control unit/flywheel) OK? Set correct air gap
yes
Test ignition system
according to flow chart
"Ignition system troubleshooting",
see Service Manual
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Technical Information 01.2010 Page 11
5.1.5 Engine stops suddenly
Engine stops suddenly
yes
Chain saw Troubleshooting completed
OK?
Check fuel path no
Repair fuel
(fuel pick-up body, tank vent, fuel Fuel path system
hoses) OK?
yes
Re-bend spade terminal on both
Connection sides (b 5.3)
Check plug connection on control unit OK? and/or replace wiring harness
yes
Check start detection Replace switching device
(micro switch, actuating lever) no if necessary
Mechanically
clean if necessary OK?
yes
Check start detection, wiring harness Are target values attained? Repair switching device and/or
and plug connections wiring harness or replace if
(b 5.6,b 5.7)
necessary
yes
Check solenoid valve Are target values Replace carburetor
attained? (b 5.5)
yes
Check engine for leaks
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)m~ge 12 Technical Information 01.2010
5.1.6 Maximum speed not reached
Maximum speed less than
12,500 rpm
Check the air filter and spark arresting
screen in the muffler – clean or
replace it if necessary
Check chain tension and
chain lubrication
Carry out five uniform cuts to length
(speed between yes
8,000 rpm and 11,200 rpm Maximum speed greater Troubleshooting completed
approx. 11.8 in. (30 cm) log diameter) than 12,500 rpm?
Re-bend spade terminal on both
no sides
Connection
Check plug connection on control unit OK and/or replace wiring harness
yes
Check start detection, wiring harness
and plug connections no
Are target values attained? Repair switching device and/or
(b 5.6,b 5.7) wiring harness or replace if
necessary
yes
Look for a fault in the fuel path,
check engine for leaks
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Technical Information 01.2010 Page 13
5.2 Ohmmeter and plug connections
An ohmmeter (multimeter) with a diode tester is
required for the following test procedures.
To ensure a reliable contact:
– Use appropriate test probes
– Do not widen or bend plugs and connector tags
– Unplug and plug in plug connections by hand
whenever possible in the direction of the
219TI075 KN
connector tags – do not insert them on a slant or
tilt or widen them
– Plug must be seated firmly . Open the latch and lift the spade terminal out of
the connector housing
5.3 Plug connection to control unit
. Clean dirty contacts with a brush
A reliable connection must be ensured for
communication between control unit, switching
device and solenoid valve. If communication
between control unit and solenoid valve is
interrupted or faulty, the control unit does not initiate
an ignition spark. Thus if there is no ignition spark,
first check the plug connections and wiring harness
between control device and solenoid. a
. Remove the fan housing
. Remove any coarse dirt from around the control
219TI076 KN
unit and the plug
. Re-bend spade terminal on both sides
(Distance a 0.01 in...0.012 in.
0.2 mm...0.3 mm)
1.
1
2.
219TI074 KN
3.
. Disconnect the plug (1) from the control unit
219TI077 KN
1. Lift the catch
2. Unplug the plug in the direction of the
connector tags
. Insert spade terminal in connector housing
3. Remove plug Red wire on the left,
If the plug connection is accidentally tilted, twisted or black wire (short circuit wire) on the right
widened when unplugging the plug, the following
additional steps are necessary:
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5.4 Connecting the M-Tronic test lead to the
diagnostic jack
2
1
219TI078 KN
2
1
219TI048 KN
. Close connector housing – latch (1) must
engage the retaining lug (2) – replace connector
housing, if necessary . Remove bushing (1)
. Remove stopper (2) – diagnostic jack is
accessible
2.
219TI079 KN
1.
219TI049 KN
. Press the plug (1) straightly and firmly into the
recess on the control unit – do not insert it on a
slant or tilt it
. Connect M-Tronic test lead 5910 840 0903 to
1. Align plug the diagnostic jack
2. Press on plug After disconnecting the test lead, reseal the
diagnostic jack with the stopper.
5.5 Checking the solenoid valve
5.5.1 Measure resistance
. Set Master Control Lever™ to position F
. Connect M-Tronic test lead 5910 840 0903 to
the diagnostic jack
. Measure resistance between the plugs of the
M-Tronic test lead
Target value: between 28 and 42 ohms
If the target value is not attained, check electrical
leads for interruption, short to voltage and short to
ground.
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Technical Information 01.2010 Page 15
5.5.2 Checking the switching function
. Set Master Control Lever™ to position STOP 0
. Connect M-Tronic test lead 5910 840 0903 to
the diagnostic jack
Apply a 9 V test voltage (E-Block / 6LR61):
219TI052 KN
. Disconnect the plug from the solenoid valve
. Position the filter base and fasten it with a nut on
the air valve side – to secure the switch shaft
219TI050 KN
(Master Control Lever™)
. Remove the fan housing
. Black plug on the negative pole . Disconnect the plug from the control unit,
see b 5.3
. Red plug on the positive pole – when the circuit
. Set Master Control Lever™ to position Start }
is made, the solenoid valve should click (switch)
– always make the circuit only briefly, to avoid . Connect M-Tronic test lead 5910 840 0903 to
damaging the solenoid valve the diagnostic jack
. If the solenoid valve fails to switch – continue
with "Checking the wiring harness" Connect M-Tronic test lead to Multimeter:
. If the solenoid valve does not switch and the . Insert black plug in "com" / "ground" jack
wiring harness is intact – replace carburetor . Insert red plug in "volt" / "ohm" jack
5.6 Checking the start detection function . Set multimeter to "diode test"
. Remove air filter, spacer flange, baffle and filter Test diode on micro switch – follow the direction
base in the multimeter Instruction Manual:
If the micro switch (switching device) is intact,
readings will match the following target values:
– Master Control Lever™ in position Start } –
measurement in direction of flow
Target value: 0.3 volts to 0.7 volts (direction of
flow)
1 1 – Master Control Lever™ in position F – reverse-
2
2 biased measurement
219TI051 KN
Target value: 1.2 volts to infinity – observe
display, e.g., display [O.L.] or [1.] (reverse bias)
If the target values are not attained, replace the
. Check micro switch (1) and lever (2) – does the
micro switch (switching device).
lever actuate the micro switch?
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)m~ge 16 Technical Information 01.2010
5.7 Checking the wiring harness
. Remove the fan housing
. Remove air filter and spacer flange 6
. Set Master Control Lever™ to position STOP 0
. Disconnect the plug from the control unit,
see b 5.3
219TI080 KN
3
. Measure the resistance between lug (3) and
screw (6) at the control unit
2 Target value: < 10 ohms
If target values are not attained, check collar screw,
nut, lug and screw for continuity and secure fit – if
necessary, clean collar screw, nut and screw and
tighten them to the specified tightening torques.
5
219TI054 KN
3 4
. Measure the resistance between connection (2)
(black wire) and lugs (3), (4) as well as
eyelet (5)
Target value: < 10 ohms
If target values are not attained, check electrical
leads for interruption – replace wiring harness,
if necessary.
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Technical Information 01.2010 Page 17
. Connect M-Tronic test lead 5910 840 0903 to
the diagnostic jack 1
2 2
219TI057 KN
2
219TI055 KN
. Disconnect the plug (1) from the solenoid valve
. Pull off the carburetor toward the rear until the
. Measure the resistance between connection (2) bolts (2) are accessible
(black wire) and the red plug (3) of the
. Remove bolts (2)
diagnostic cable
. Remove switching device (3) and place it on the
Target value: < 10 ohms
shroud
. Remove carburetor
4 1
5
219TI056 KN
. Measure the resistance between connection (4)
(red wire) and the black plug (5) of the
diagnostic cable
Target value: < 10 ohms
If the target values are not attained, check the 2
contact surfaces between eyelet and torsion spring
219TI058 KN
as well as electrical leads for interruption – replace
wiring harness and/or switching device, if
necessary. . Take wiring harness out of the guides (arrows)
5.8 Carburetor and switching device . Disconnect plug connection (1)
. Unscrew nut (2) and remove terminal socket
5.8.1 Remove carburetor and switching device
The steps specific to the M-Tronic are listed below:
. Remove bushing and pull the stopper out of the
diagnostic jack
. Remove air filter, spacer flange, baffle and filter
base
. Disconnect throttle cable
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)m~ge 18 Technical Information 01.2010
5.8.2 Carburetor service work
Service work on metering diaphragm, pump
diaphragm, inlet needle, lever, gaskets, choke 3
shutter and air valve housing same as standard MS
441 carburetor.
4 1
4
5
2 2
1
219TI059 KN
219TI081 KN
7 6
Position of the special bolt (1) must not be changed,
because otherwise the factory default setting will no . Press the plug (1) firmly into the recess of the
longer be correct and this can lead to impaired solenoid valve and simultaneously press the
engine performance. wires into the cable guide (2) – red wire must
Solenoid valve (2) must not be dismantled. face filter base
. Press the wiring harness into the recess (3) until
the shrink tube is flush with it – red wire on top
5.8.3 Installing the switching device
. Lay the wiring harness flat in the guides (4)
1 . Press together the plug and terminal socket (5)
as far as they will go – slide insulating tube over
the plug connection
3 . Tighten collar screw (6) and nut to the specified
tightening torque
2 2 . Lug (7) of the ground wire must touch the
supporting rib
219TI060 KN
. Position switching device (1)
. Screw in bolts (2) and torque to 1.48 lbf.ft
(2.0 Nm)
. Refit carburetor
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Technical Information 01.2010 Page 19
5.9 Wiring harness
5.9.1 Removing the wiring harness
. Remove the fan housing
. Remove air filter, spacer flange, baffle and filter
base
. Unplug the spark plug boot
219TI064 KN
1
. Lay short circuit wire flat in the guides – white
marking (arrow) on the wire must be on the right
end of the guide
. Connect short circuit wire at the switch shaft
. Further assembly as previously
219TI062 KN
2
5.10 Setting the flywheel air gap
. Remove pre-separator
. Remove ignition lead (1) from cable guide
. Disconnect the plug (2) from the control unit,
see b 5.3
. Detach bushing (3)
. Remove switch shaft (Master Control Lever™)
from the carburetor support mount
. Disconnect short circuit wire at the switch shaft
5.9.2 Installing the wiring harness
219TI065 KN
3
Set the air gap between the arms of the control unit
1 and the pair of magnetic poles marked "N" / "S" on
the flywheel – use setting gauge 1111 890 6400
Air gap: 0.012 in (+0.002/-0.004 in)
0.30 mm (+0.05 mm/-0.10 mm)
219TI063 KN
. Attach bushing (3)
. Press the plug (2) straightly and firmly into the
recess on the control unit, see b 5.3
. Lay first the red wire and then the black wire flat
in the cable guide
. Lay ignition lead (1) in the cable guide
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)m~ge 20 Technical Information 01.2010
5.11 Calibrating the control unit
If the control unit or carburetor is replaced during
servicing, the M-Tronic must be calibrated.
. Remove the saw chain and guide bar
. Install chain sprocket cover
. Set Master Control Lever™ to Start }
. Start chain saw – do not blip the throttle trigger
. Let the engine run for at least 60 seconds in the
start position and then move the Master Control
Lever™ from the position Start } to STOP 0 –
calibration is finished
The control unit is adjusted to the carburetor while
the engine runs in the position Start }. The engine
must be switched off immediately for the information
to be stored in the control unit.
5.12 Muffler, plugs
Do not refit used plugs; push new plugs straight in
with a blunt tool – do not damage plugs.
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)qechnic~l=fnform~tion=MNKOMNM=========================================================================m~ge=ON
5.13 Tightening torques
219TI083 KN
Fastener Thread size Part(s) Tightening torque Pcs. Comment
Collar screw M5x14 Collar screw / housing / 6.64 lbf.ft (9.0 Nm) 1
crankcase
Collar nut M5 Collar screw / ring lug 2.58 lbf.ft (3.5 Nm) 1
Screw M5x16 Housing / crankcase 5.53 lbf.ft (7.5 Nm)
Screw M4x12 Switching device / carburetor 1.48 lbf.ft (2.0 Nm) 2 1)
Screw M4x20 Control unit / ignition module / 2.95 lbf.ft (4.0 Nm) 2 1)
crankcase
Remark
1) Before reassembly, coat microencapsulated screws with medium strength thread-locking adhesive,
e.g., Loctite 243
Additional tightening torques are listed in the
Service Manual for the STIHL MS 441.
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)m~ge 22 Technical Information 01.2010
5.14 Repair times
Type of repair MS 441 C-M
The specified repair times apply for trained and 1 Replace crankcase, crankcase 140
qualified personnel as well as for properly equipped gasket or re-seal crankcase.
repair shops. Includes air leak test.
The repair times are specified in minutes 2 Replace engine housing or 15
cylinder shroud.
3 Replace crankshaft main 130
bearing(s). Includes air leak test.
4 Replace crankshaft seal(s). 60
Includes air leak test.
5 Perform engine air leak test. 40
6 Replace cylinder and/or piston. 80
Includes air leak test and repair
of components causing failure.
7 Replace control unit or flywheel. 30
Includes stop circuit test.
8 Replace fuel tank line, tank vent, 25
or fuel pick-up body.
9 Replace intake manifold or 30
intake flange, including leak test.
10 Repair or replace carburetor. 35
Includes fuel system testing.
11 Replace fuel tank housing. 35
12 Replace oil pick-up/delivery line. 30
Includes oil output test.
13 Replace oil pump and/or drive 30
gear. Includes oil output test.
14 Replace rear handle frame or 30
handle housing.
15 Repair or replace rewind starter. 20
16 Repair or replace clutch, clutch 20
shoes or clutch springs.
17 Repair chain brake, including 35
check for proper function.
18 Replace muffler. 15
19 Replace air filter or filter 15
housing.
22 Repair or replace stop switch. 20
Includes circuit testing.
23 Replace throttle cable. 35
24 Replace carburetor housing. 40
25 Replace front handle 20
26 Replace solenoid valve or 40
M-Tronic wiring. Includes
diagnostic and function tests.
40 Miscellaneous repairs and other 15
repairs not listed.
45 Handling allowance only-no labor. 10
50 No labor. 0
© ANDREAS STIHL AG & Co. KG, 2010 Technical Documentation
D1/MTK-bl
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Extracted from the manufacturer's 2012 service catalogue. Most of these PDFs embed fonts with a shifted character map, so the text above was recovered rather than copied — read it as a faithful but imperfect transcription, and treat the page image above each block as the authority where the two disagree — the figures exist only there, because they are vector drawings that text extraction cannot keep.