System Actuators - Triumph 2012 Tiger 800 Service Manual

Fuel System/Engine Management

System Actuators

In response to signals received from the sensors, the ECM
controls and directs messages to a series of electronic and
electro-mechanical actuators. The function and location of
the actuators is given below.
Throttle stepper motor - situated between
the th rottle bodies of cylinders two and three.
The throttle stepper actuates a cam/lever
which ca uses variations in the closed throttle
position. Although used primari ly to ensure
target idle speed
increases throttle opening when the engine is
cold.
Canister purge valve <California models
•
only> - situated in the vapour return line
between the carbon canister and the throttle
bodies. The purge valve controls the return of
vapour which has been stored in the carbon
canister during the period when the engine is
switched off. The valve is 'pulsed' by the ECM
to give control over the rate at which the
ca nister is purged.
Injectors - located on the th rottle body. The
•
engine is fitted with three injectors. The spray
pattern of the injectors is fixed but the length
of time each injector can remain open is
variable according to operating conditions.
The duration of each i njection is calculated by
the ECM using
various sensors in the system.
Ignition coils - plug-top coils are located in
•
the cam cover. There are three coils fitted,
one for each spark plug. The ECM controls
the point at which the coils are switched on
and off. In calculating the switch-on time, the
ECM a llows sufficient time for the coils to
charge to a level where a spark ca n be
produced. The coils are switched off at the
point of ignition, the timing of which
optimised for good engine performance.
EMS main relay -
battery. When the ignition is switched on, the
EMS mai n relay is powered up to provide a
stable voltage supply for the ECM. When the
ignition is turned off, the ECM carries out a
power down sequence during which the EMS
main relay remains powered by the ECM for
1 minute. The ECM power down sequence
includes: writing the adaption data to ECM
memory and referencing the position of the
throttle stepper motor.
Fuel pump - located i nside the fuel tank. The
•
electric pump delivers fuel
system, via a pressure regulator, at a constant
3 bar pressure. The pump is run contin uously
1 0.18
is maintained, it also
data received from the
is
situated behind the
into the fuel
SeiVice Manual Tiger 800 and Tiger 800XC
-
when the engine is operating and is a lso run
briefly when the ignition is first switched on
to ensure that 3 bar is avai lable to the system
as soon as the
pressure is controlled by a reg u lator also
situated i nside the fuel tan k.
Cooling fan - located behind the radiator.
The ECM controls switching on and off of the
cooling fan in response to a signal received
from the coolant tem perature sensor. When
the coolant temperatu re rises to a level where
the cooling effect
insufficient, the cooling fan is turned on by
the ECM. When the coolant tem peratu re falls
sufficiently, the ECM turns the cool i ng fan off.
The fan only becomes operational when the
engine is ru nning. lt will not operate at any
other time.
Note:
In this system, the starter lockout system
•
(clutch switch,
sidestand switch> all operate through the
engine management ECM.
engine is cra n ked. Fuel
of natu ra l airflow is
gear position sensor,
\