Ski-Doo 2005 MACH Z, Руководство по ремонту

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Section 04 ENGINE MANAGEMENT (SDI)
Subsection 01 (OVERVIEW)
The tether cord cap contains a magnet and a ROM
chip. The magnet actually closes the reed switch
inside the post which is the equivalent of a me-
chanical ON/OFF switch. The chip has a unique
digital code.
NOTE: Actually, it is the memory of the ECM
which is programmed to recognize the digital
code of the tether cord cap. This is achieved with
the VCK (Vehicle Communication Kit) (P/N 529
035 981). Refer to their operation manual or help
system to program a tether cord cap.
529 035 981
The system is quite flexible. Up to 8 tether cord
caps may be programmed in the memory of the
ECM. They can also be erased individually.
NOTE: If desired, a tether cord cap can be used
on other vehicle equipped with the DESS. It only
needs to be programmed for that vehicle.
When starting the engine with a tether cord cap
on the post, the DESS is activated and will emit
audible signals:
– 2 short beeps indicate a working tether cord
cap. Vehicle can be driven.
– short repetitive beeps indicates a wrong tether
cord cap is being used or that something is de-
fective. Vehicle can not be driven.
Engine Starting
If the ECM recognizes a valid tether cord cap, it
allows engine to rev above 3000 RPM.
ROTAX ELECTRONIC REVERSE
(RER)
There is 3 main components used for the RER
system: the START/RER switch, the ECM and the
crankshaft position sensor.
The ECM receives signals from the crankshaft po-
sition sensor (CPS) for the following functions:
– Forward engine rotation.
– Reverse engine rotation.
– Crankshaft position and engine RPM.
The ECM recognizes a signal sent by the
START/RER switch.
When switch is activated and engine is not run-
ning, ECM allows normal engine starting.
When switch is activated and engine is running,
ECM cuts off ignition. Therefore, engine RPM
gradually drops.
When engine reaches a low
threshold RPM, ECM sends an ignition spark at
a great advance creating a thrust which reverses
engine rotation.
Under a threshold low RPM or above drive pulley
engagement speed, the RER function is disabled.
Nothing takes place when pressing START/RER
button.
MONITORING SYSTEM
The ECM monitors the electronic components of
the engine management system and other com-
ponents of the electrical system.
When a fault occurs, it sends a signal to the check
engine LED or also to the beeper to inform the
driver of a particular condition. Refer to the DIAG-
NOSTIC PROCEDURES.
Low-Oil Level Warning Device
When the oil falls under a certain level, the low oil
level LED will be illuminated. The beeper will also
be activated intermittently.
High Coolant Temperature Warning
Device
When the coolant temperature is getting too high,
the ECM sends out signals to the beeper and the
high temperature LED.
Limp Home Mode
Besides the signals as seen above, the ECM may
automatically set default parameters to ensure the
adequate operation of the vehicle if a component
of the engine management system is not operat-
ing properly.
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